https://www.clinfowiki.org/wiki/api.php?action=feedcontributions&user=Phamnh&feedformat=atomClinfowiki - User contributions [en]2024-03-28T19:43:40ZUser contributionsMediaWiki 1.22.4https://www.clinfowiki.org/wiki/index.php/The_Blockchain_in_HealthcareThe Blockchain in Healthcare2018-10-19T03:17:43Z<p>Phamnh: </p>
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<div>The blockchain is an idea centered around the concept of a secure, digital ledger system that provides a system for efficient, auditable transactions of almost any type between entities <ref>Tapscott D, Tapscott A. Blockchain Revolution: How the Technology Behind Bitcoin Is Changing Money, Business, and the World. United States: Portfolio; 2016. 1-368 p.</ref>. All information related to blockchain transactions is at once both independently verifiable by all (even outside) parties as correct and also inscrutable to entities without explicit permission. The first and probably most well-known implementation of blockchain technology is [https://bitcoin.org Bitcoin] <ref name="BTC">Nakamoto S. Bitcoin: A Peer-to-Peer Electronic Cash System. WwwBitcoinOrg [Internet]. 2008;9. Available from: https://bitcoin.org/bitcoin.pdf</ref>, but there has been a massive expansion of blockchain use-cases since Bitcoin's initial introduction.<br />
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== What is the Blockchain? ==<br />
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First, it should be clear that there is no one blockchain to rule them all. "The Blockchain," as it is often referred, really is a concept of a series (chain) of interrelated sets (blocks) of encrypted information. Hence a chain of blocks, or blockchain. There are many such blockchains in existence, and one could choose to do transactions on any one of them or create a new blockchain.<br />
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An important aspect of most blockchains is that they are designed to be maintained on a distributed network of multiple nodes. Each node holds a complete copy of the blockchain and adds each sequential new block as it is created. This system allows every transaction on the blockchain to be verified by any or all of the nodes in the network, and also makes it very difficult for the information held in the blockchain to become lost or unavailable if any one or even most of the nodes go offline.<br />
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Transactions that are set to be added to the blockchain are added to the newest block as soon as it is created. This makes the continued existence of the blockchain dependent on the creation of new blocks. There are several main methods for the creation of new blocks on the network, and the choice of method depends somewhat on the purpose of the blockchain in question. Bitcoin, the first cryptocurrency, uses a method called [https://en.wikipedia.org/wiki/Proof-of-work_system Proof of Work System (Wikipedia)]:<br />
* In the traditional Proof of Work System, each block validator, or "miner," competes to validate the block by processing a task. The winner is the first person to complete this task. The chance of completion of the task is random based on a hash function, but increases with the more "work" a person puts into the task. The system can automatically vary the difficulty of the task to limit the speed of block generation. The winner is credited for his/her work by a small amount of currency. <br />
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The blockchain has moved beyond simply processing transactions of cryptocurrency such as Bitcoin. Any data that can be encoded into a cryptographic [https://en.wikipedia.org/wiki/Hash_function hash] can be added to a blockchain. Various different ideas have been proposed, and I will not attempt to list them here, but they are wide ranging. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0<ref>Swan, M. (2015). Blockchain: Blueprint for a new economy: " O'Reilly Media, Inc."</ref>. Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education.<br />
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=== Blockchain Development Groups ===<br />
Certainly a non-exhaustive list . . .<br />
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* [https://bitcoin.org/en/ Bitcoin]<br />
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* [https://hyperledger.org The Hyperledger Project]<br />
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* [https://ethereum.org The Ethereum Project]<br />
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* [https://r3cev.com/blog/2016/4/4/introducing-r3-corda-a-distributed-ledger-designed-for-financial-services The CORDA Platform]<br />
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* [http://www.muskokagroup.org/ The Muskoka Group]<br />
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* [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab The ONC Tech Lab]<br />
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== Blockchain Use Cases ==<br />
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=== Cryptocurrency ===<br />
Bitcoin (BTC) was the first cryptocurrency based on the blockchain and was developed by someone calling himself (or herself) Satoshi Nakamoto. The protocol was introduced in 2008 after the publication of a white paper<ref name="BTC" /> describing the algorithm and the mechanisms for generation and distribution of BTC. At this point there are hundreds of cryptocurrencies in circulation according to [http://wikipedia.org Wikipedia], many of which are based on the Bitcoin blockchain, but only a few have gone into widespread use<ref>https://en.wikipedia.org/wiki/List_of_cryptocurrencies</ref>.<br />
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=== Smart Contracts ===<br />
One of the major potential functions of blockchain technology is through the creation of smart contracts. Various components of contracts, including proof of the involved parties, requirements for completion, and actions upon completion of the contract can be encoded in blocks. These can then be added to a blockchain and become available for independent verification, which can even lead to automatic processing of contracts when their requirements have been fulfilled.<br />
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Smart contracts are scripts which have various rules and logic that automatically execute when those rules are met. Smart contracts allow heavily automated workflows between transacting parties in the network while maintaining anonymity. Once the contract has been executed, one can take custody over assets or pre-defined payments can be issued. <ref>Christidis, K & Devetsikiotis, M. (2016, May 10). Blockchains and Smart Contracts for the Internet of Things. IEEE Access, 4, 2292-2303. doi: 10.1109/ACCESS.2016.2566339</ref> They are importantly different in the sense that they are stored on a distributed network and they can be verified as true without knowledge of the contract specifications <ref>https://bitsonblocks.net/2016/02/01/a-gentle-introduction-to-smart-contracts/</ref>.<br />
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[https://ethereum.org The Ethereum Project] was one of the first to introduce the concept of smart contracts using their alternative blockchain and currency token, [https://www.ethereum.org/ether ether].<br />
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=== Securities Exchanges and Finance ===<br />
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One of the hottest arenas for blockchain development currently is in the financial markets, an extension of the original cryptocurrency use cases for the blockchain. Multiple stock markets and other financial firms have initiated investigations and pilot projects into the feasibility and utility of the blockchain for contracts and tracking of financial instruments. NASDAQ has been one of the first major markets to put blockchain technology into use, and has released some information on its implementation, called Linq <ref>http://ir.nasdaq.com/releasedetail.cfm?releaseid=948326</ref><ref>http://www.coindesk.com/hands-on-with-linq-nasdaqs-private-markets-blockchain-project/</ref>. The cryptocurrency website [http://www.coindesk.com Coindesk] has also produced a list of 10 exchanges using or investigating blockchain technologies<ref>http://www.coindesk.com/10-stock-exchanges-blockchain/</ref>.<br />
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Additionally, financial firms such as Visa have been experimenting with the blockchain for keeping track of transactions as well as with proof of concept applications such as remittance<ref>http://www.coindesk.com/hands-on-with-visa-europes-bitcoin-remittance-app/</ref>.<br />
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== Advantages and Disadvantages of Blockchain ==<br />
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Blockchain is a novel concept and is being explored in various sectors. While there may be several applications and limitations of this technology in future, some of them are highlighted below<ref>Fauvel, W. (2017, August 11). Blockchain Advantage and Disadvantages. Medium. Retrieved from: https://medium.com/nudjed/blockchain-advantage-and-disadvantages-e76dfde3bbc0</ref>:<br />
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=== Pros: ===<br />
# Distributed: There is no single owner of the database. As anyone can contribute and be a part of the network, the risks of data tampering and fraud are minimal. As Nakamoto <ref name="BTC" /> mentioned, as long as the majority of nodes are honest, a random attacker would not be able to alter the history.<br />
# Trustless: As every node in the network will have a copy of the blockchain and they verify the transactions independently. Hence, this system allows transaction even if the parties don't trust each other.<br />
# Immutable: Once the transaction is verified and embedded in the blockchain, it is almost impossible to undo it, and the complexity increases with time as more blocks are added downstream. This allows keeping a track of accurate events that occurred through the history.<br />
# Decentralized: There is no middleman like banks or data owners. This helps avoid manipulation of the market by the owners.<br />
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=== Cons: ===<br />
# Waste of resources: As several nodes are running and utilizing a huge amount of computing power and electricity to verify and maintain the blockchain, there is more than required redundancy. <br />
# Higher cost for less value: With time, the use of network increases and the complexity of the hashing algorithm also increases. Hence, more resources are required for the same amount of work. This increases the cost of work and transactions gets slower, as miners prioritize the transactions with higher incentives causing a backlog the transactions with smaller values. <br />
# Difficulty to keep up with the size of the block: As the size continues to grow along with the complexity to solve the calculation, new nodes with smaller computing power will have difficulty joining the network and likewise, the older and slower nodes will gradually fade with decreasing incentive for the work. Hence, like Darwin’s theory of the "survival of the fittest", a few larger nodes will dominate the network creating more and more centralization of the system. <br />
# Speculative market: Due to the lack of proper regulation of this system, the market is subject to a great volatility and thus making it risky for investors. <br />
# Immutable smart contracts: As there are clear advantages of having permanent and immutable records, at the same time, there is a bitter flipside to this. For example, if there is a flaw with code that can compromise the system, it is also irreparable and creates the opportunity for the attackers to exploit the same flaw repetitively in future. As time progresses, the capability of repairing the error will be even more complex.<br />
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=== Possible Solutions: ===<br />
* The issues with resource wastefulness and diminishing return of investment are mainly an issue with Proof-of-Work Systems, and can be improved with new blockchain innovations such as [https://en.bitcoin.it/wiki/Proof_of_Stake Proof of Stake (Bitcoin Wiki)] or blockchain scaling<ref>Croman, Kyle, et al. "On scaling decentralized blockchains." International Conference on Financial Cryptography and Data Security. Springer, Berlin, Heidelberg, 2016.</ref><br />
** There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake<ref>Siim, Janno. "Proof-of-Stake."</ref>. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker.<br />
** Currently, all computers that participate in mining a blockchain process every transaction. This is very slow and resource wasteful. A solution to this is to calculate how many computers will be needed to validate a new block, and give the task of verifying a transaction to those computers. This will allow parallel processing (scaling) of "blocks" and speed up transactions. At this point, the details behind how to manage this division of tasks without compromising security still being worked out.<br />
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== Potential Use Cases in Healthcare ==<br />
Though there has yet to be a breakthrough report or use-case for blockchain technology in healthcare, there are many potential ways that the blockchain could be implemented within the current healthcare structure. Any list will likely be incomplete, but these examples represent some of the published and available literature on blockchain implementations in health.<br />
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=== Health Information Exchange (HIE) ===<br />
One major area that blockchains may be able to facilitate is the secure access to and communication of patient health records between individuals and institutions. There have been multiple white papers published on the topic, including groups from the Mayo Clinic <ref>Peterson K, Deeduvanu R, Kanjamala P, Boles K. A Blockchain-Based Approach to Health Information Exchange Networks. (1):1–10.</ref> and MIT <ref>Ekblaw A, Azaria A, Halamka JD, Lippman A, Original I, Vieira T. A Case Study for Blockchain in Healthcare: “ MedRec ” prototype for electronic health records and medical research data MedRec: Using Blockchain for Medical Data Access and Permission Management [Internet]. 2016. Available from: https://www.healthit.gov/sites/default/files/5-56-onc_blockchainchallenge_mitwhitepaper.pdf</ref> who described a system for patient information exchange based on blockchain technology that would allow patient-controlled access to records across institutions using HL7 Fast Healthcare Interoperability Resources ([[FHIR]]), [http://json.org JSON], or other encoding system. In these models the actual health care data are not encoded in the blockchain, but are merely references pointing to where the data reside, such as at institutions or in a "data lake" <ref>Linn LA, Koo MB. Blockchain For Health Data and Its Potential Use in Health IT and Health Care Related Research. 2014;1–10.</ref>. Similarly, a group out of China described an app called Healthcare Data Gateway (HGD) that allows patients to view and directly control rule-based access to their health records with a smart phone interface and authentication provided by a blockchain network <ref>Yue X, Wang H, Jin D, Li M, Jiang W. Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst [Internet]. 2016 Oct;40(10):218. Available from: http://dx.doi.org/10.1007/s10916-016-0574-6</ref>. These ideas support the concept of patient-owned medical data, and would have the effect of decentralization of medical records in ways that are as yet undetermined.<br />
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=== Health Research Integrity ===<br />
Academic research is a major driver of advances in health care, but in the setting of limited funding and publication pressures on researchers significant concerns have been raised regarding research integrity<ref>Titus SL, Wells J a, Rhoades LJ. Repairing research integrity. Nature [Internet]. 2008 Jun 19;453(7198):980–2. Available from: http://www.ncbi.nlm.nih.gov/pubmed/18563131</ref>. Organizations such as [http://clinicaltrials.gov ClinicalTrials.gov] and others have been developed to help drive researchers to define endpoints and analysis prior to conducting clinical trials and other studies. As it represents an immutable, verifiable record of events and transactions, the blockchain has been proposed as a potential decentralized resources for helping to ensure biomedical research integrity. Benjamin Carlisle<ref>Carlisle BG. Proof of prespecified endpoints in medical research with the bitcoin blockchain [Internet]. 2014. Available from: http://www.bgcarlisle.com/blog/2014/08/25/proof-of-prespecified-endpoints-in-medical-research-with-the-bitcoin-blockchain/</ref>, followed by several researchers from the UK<ref>Irving G, Holden J. How blockchain-timestamped protocols could improve the trustworthiness of medical science. F1000Research [Internet]. 2016;5:222. Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4866630/</ref>, proposed in 2014 that researchers could use the blockchain to record pre-specified aspects of their projects, including the study design, analysis plan, and data structure, among others, which could later be verified by consumers of the literature to decrease bias that may be introduced in post-hoc analysis<ref>Slade E, Drysdale H, Goldacre B, COMPare Team. Discrepancies Between Prespecified and Reported Outcomes. Ann Intern Med [Internet]. 2016 Mar 1;164(5):374. Available from: http://www.ncbi.nlm.nih.gov/pubmed/26720309</ref>. The blockchain also offers the potential ability to verify the integrity of actual research data and analysis by outside observers, even if the data themselves are not made publicly available. These types of implementations may lead to improvements in both the integrity of biomedical research as well as bolster public trust in medical research.<br />
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=== Personal Health Records ===<br />
This concept dovetails with the idea of HIE using the blockchain, but focuses more on the secure maintenance of a personal health record (PHR) by patients. No production PHR has been released based on this technology, but concepts such as MedVault <ref>Baxendale G. Can Blockchain Revolutionise EPRs? [Internet]. Vol. 58, ITNOW. 2016. p. 38–9. Available from: http://itnow.oxfordjournals.org/lookup/doi/10.1093/itnow/bww017</ref> use alternative blockchains such as [http://www.Colu.com Colu] to store patient data directly on the blockchain. Others such as [https://devpost.com/software/ehealthwallet eHealthWallet] have also developed prototype PHRs based on the blockchain. Patients could then share or authorize doctors and other health entities to access and modify their data.<br />
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The majority of the proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference<ref>Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230</ref><ref>Yue, X., Wang, H., Jin, D., Li, M., & Jiang, W. (2016). Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst, 40(10), 218. doi:10.1007/s10916-016-0574-6</ref>. <br />
* In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care.<br />
* As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed.<br />
* A blockchain-enabled smart contracts controlled by the patient can be used to authorize direct sharing of medical record between institutions. Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
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Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability<ref>Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230</ref>: <br />
* Digital access rules: The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application<br />
* Data aggregation: Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health<br />
* Data liquidity: Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc.<br />
* Patient identity: Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems<br />
* Data immutability: Since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time.<br />
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There are several limitations of the current state of technologies for blockchain-based personal health records:<br />
* The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. Proposed solutions include:<br />
** Validate data using a different approach to consensus such as proof-of-stake. <br />
** Store a summary of, instead of a complete clinical report.<br />
** Patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
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* A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A few solutions to this problem has been proposed:<br />
** Use permissioned (member-only) blockchain to avoid public exposure.<br />
** Basic demographic information stored on a block chain can also be encrypted to prevent access.<br />
** Store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
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* Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. <br />
** Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. <br />
** Patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
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* The largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. To overcome this, a few proposals have been made:<br />
** Expand federal incentives to patient-controlled medical record.<br />
** Researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
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=== Storage of Health Care Data ===<br />
Most of the previous examples use the blockchain not as a direct data storage medium, but instead as a secure reference point for identities, access, and data locations. At least one group from a company called Tierion, which partners with the [http://www.2.forms.healthcare.philips.com/blockchainlabs Philips Blockchain Lab ], has produced a concept called Chainpoint<ref>Vaughan AW, Bukowski J, Wilkinson S, Sporny CM, Shea R, Allen C, et al. Chainpoint: A scalable protocol for anchoring data in the blockchain and generating blockchain receipts [Internet]. 2016. Available from: https://tierion.com/chainpoint</ref>, which proposes to use a [https://proofofexistence.com/about Proof of Existence] concept and Merkle Roots<ref>Merkle RC. PROTOCOLS FOR PUBUC KEY CRYPTOSYSTEMS. In: IEEE Symposium on Security and Privacy [Internet]. 1980. p. 122–34. Available from: http://www.merkle.com/papers/Protocols.pdf</ref> to efficiently store actual patient records on the blockchain without imposing excessive transaction demands on the system.<br />
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=== Billing and Claims Adjudication ===<br />
Blockchain system can help reduce administrative costs and time while automating claims adjudication and payment processing using smart contracts. For example - a smart contract is set up between payer or insurance company, provider, and patient such that when the patient sees a provider, or if a procedure is done, an entry is recorded in the blockchain. Based on the criteria set, the contract can automatically issue reimbursement from the payer as well as co-pay from the patient without having to wait for the insurance approval.<ref>Srinivasan, P. (2017, November 9). Healthcare Blockchain: How Smart Contracts Could Revolutionize Care Delivery. Prolifics. Retrieved from: https://www.prolifics.com/blog/healthcare-blockchain-how-smart-contracts-could-revolutionize-care-delivery</ref><br />
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=== Drug Supply Chain and Prescription Management ===<br />
Counterfeit drugs are a major problem especially in the developing country where it is estimated that about 1 in 10 medical products are counterfeit <ref>WHO. (2017, November 28). 1 in 10 medical products in developing countries is substandard or falsified. Retrieved from: http://www.who.int/en/news-room/detail/28-11-2017-1-in-10-medical-products-in-developing-countries-is-substandard-or-falsified</ref>. Ensuring the integrity of the drug and maintaining a robust audit trail is a must to ensure patient safety. Similarly, this platform can be used in prescription drug management and track history and authenticate prescriptions using smart-contracts. <br />
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=== Few Examples of Current Use Cases and Future Development ===<br />
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* MedRec- it is based on Ethereum platform and focuses on medical data management using smart contracts like managing permissions and authentication processes, data sharing in an interoperable environment between healthcare systems and maintaining an audit log. <ref>Azaria, A., Ekblaw, A., Vieira, T., & Lippman, A. (2016, August 22-24). MedRec: Using Blockchain for Medical Data Access and Permission Management. 2016 2nd International Conference on Open and Big Data (OBD). doi:10.1109/obd.2016.11</ref><br />
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* Guardtime- also focuses on medical data management and has partnered with e-Health authority of Estonia to secure the country's database of health records <ref>Ruubel M. (2016, February 12). Estonian eHealth Authority Partners with Guardtime to Accelerate Transparency and Auditability in Health Care. Retrieved from: https://guardtime.com/blog/estonian-ehealth-partners-guardtime-blockchain-based-transparency</ref>. Also, recently, MyPCR smartphone platform from Guardtime has partnered with Instant Access Medical and Healthcare Gateway in the UK for patient health data management and verification of medication adherence. <ref>Ruubel M. (2018, June 20). World’s first blockchain-supported Personal Care Record Platform launched by Guardtime and partners to up to 30 million NHS patients in the UK. Retrieved from: https://guardtime.com/blog/world-s-first-blockchain-supported-personal-care-record-platform-launched-by-guardtime-and-partners</ref> <br />
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* Blockchain Health- created for healthcare research data management where users can individually authorize the release of their health information to researchers as well as track the use of their data. <ref>BlockchainHealth. (2016). Blockchain for health research. Retrieved from: https://blockchainhealth.co/</ref><br />
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* BlockMedx- it is a startup company which intends to use the blockchain platform to transmit DEA controlled drug prescriptions from physicians to pharmacies and then to patients securely. <ref>BlockMedx. (2018). Retrieved from: https://blockmedx.com/en/</ref><br />
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* MediLedger- another pharmaceutical supply chain management startup company who has partnered with several drug manufacturers and aims to provide an open, secure and interoperable network. <ref>MediLedger. (2018). The MediLedger Project. Retrieved from: https://mediledger.com/</ref><br />
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* Drug and Pharmacy Verification - [https://devpost.com/software/veripharm VeriPharm] has developed a proof of concept that would help track and verify pharmaceuticals from the raw materials to the final product administered to patients.<br />
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* Appointment Scheduling on the Blockchain - [https://devpost.com/software/dhva-appointment-blocks dhva-apointment-blocks]<br />
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* Care Coordination - Projects such as [https://devpost.com/software/simplyvitahlth simplyvitahlth] are geared toward coordinating care between multiple providers and at different institutions to ensure that complex care pathways are being followed appropriately.<br />
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There are many more potential use-cases for blockchain technology within healthcare, and undoubtedly we will continue to see development in this area in coming years. In 2016, a consortium of sponsors led by [https://gem.co/ Gem] (Whitepaper)<ref>Wood C, Winton B, Carter K, Benkert S, Dodd L, Bradley J, et al. How Blockchain Technology Can Enhance Ehr Operability [Internet]. 2016. Available from: http://research.ark-invest.com/blockchain-and-healthcare</ref> held the first healthcare oriented blockchain conference, [https://godistributed.com/health Distributed: Health] in Nashville, TN. Similarly, the Office of the National Coordinator (ONC) Tech Lab had issued a Blockchain Challenge in July, 2016.<ref>https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab</ref><br />
* The list of submissions and awards can be found [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab here]<br />
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As the healthcare blockchain community grows, gatherings such as these will likely increase and blockchain technologies will increasingly be introduced at major medical conferences.<br />
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== References ==<br />
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Submitted by Nhat Pham<br />
[[Category: BMI512-FALL-18]]<br />
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Submitted by Sandeep Regmi<br />
[[Category: BMI512-FALL-18]]<br />
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Submitted by Ben Orwoll<br />
[[Category: BMI512-FALL-16]]<br />
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[[Category: Reviews]]<br />
[[Category: Other Technologies]]</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/The_Blockchain_in_HealthcareThe Blockchain in Healthcare2018-10-19T03:14:31Z<p>Phamnh: /* Personal Health Records */</p>
<hr />
<div>The blockchain is an idea centered around the concept of a secure, digital ledger system that provides a system for efficient, auditable transactions of almost any type between entities <ref>Tapscott D, Tapscott A. Blockchain Revolution: How the Technology Behind Bitcoin Is Changing Money, Business, and the World. United States: Portfolio; 2016. 1-368 p.</ref>. All information related to blockchain transactions is at once both independently verifiable by all (even outside) parties as correct and also inscrutable to entities without explicit permission. The first and probably most well-known implementation of blockchain technology is [https://bitcoin.org Bitcoin] <ref name="BTC">Nakamoto S. Bitcoin: A Peer-to-Peer Electronic Cash System. WwwBitcoinOrg [Internet]. 2008;9. Available from: https://bitcoin.org/bitcoin.pdf</ref>, but there has been a massive expansion of blockchain use-cases since Bitcoin's initial introduction.<br />
<br />
<br />
<br />
== What is the Blockchain? ==<br />
<br />
First, it should be clear that there is no one blockchain to rule them all. "The Blockchain," as it is often referred, really is a concept of a series (chain) of interrelated sets (blocks) of encrypted information. Hence a chain of blocks, or blockchain. There are many such blockchains in existence, and one could choose to do transactions on any one of them or create a new blockchain.<br />
<br />
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An important aspect of most blockchains is that they are designed to be maintained on a distributed network of multiple nodes. Each node holds a complete copy of the blockchain and adds each sequential new block as it is created. This system allows every transaction on the blockchain to be verified by any or all of the nodes in the network, and also makes it very difficult for the information held in the blockchain to become lost or unavailable if any one or even most of the nodes go offline.<br />
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Transactions that are set to be added to the blockchain are added to the newest block as soon as it is created. This makes the continued existence of the blockchain dependent on the creation of new blocks. There are several main methods for the creation of new blocks on the network, and the choice of method depends somewhat on the purpose of the blockchain in question. Bitcoin, the first cryptocurrency, uses a method called [https://en.wikipedia.org/wiki/Proof-of-work_system Proof of Work System (Wikipedia)]:<br />
* In the traditional Proof of Work System, each block validator, or "miner," competes to validate the block by processing a task. The winner is the first person to complete this task. The chance of completion of the task is random based on a hash function, but increases with the more "work" a person puts into the task. The system can automatically vary the difficulty of the task to limit the speed of block generation. The winner is credited for his/her work by a small amount of currency. <br />
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The blockchain has moved beyond simply processing transactions of cryptocurrency such as Bitcoin. Any data that can be encoded into a cryptographic [https://en.wikipedia.org/wiki/Hash_function hash] can be added to a blockchain. Various different ideas have been proposed, and I will not attempt to list them here, but they are wide ranging. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0<ref>Swan, M. (2015). Blockchain: Blueprint for a new economy: " O'Reilly Media, Inc."</ref>. Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education.<br />
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=== Blockchain Development Groups ===<br />
Certainly a non-exhaustive list . . .<br />
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* [https://bitcoin.org/en/ Bitcoin]<br />
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* [https://hyperledger.org The Hyperledger Project]<br />
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* [https://ethereum.org The Ethereum Project]<br />
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* [https://r3cev.com/blog/2016/4/4/introducing-r3-corda-a-distributed-ledger-designed-for-financial-services The CORDA Platform]<br />
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* [http://www.muskokagroup.org/ The Muskoka Group]<br />
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* [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab The ONC Tech Lab]<br />
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== Blockchain Use Cases ==<br />
<br />
=== Cryptocurrency ===<br />
Bitcoin (BTC) was the first cryptocurrency based on the blockchain and was developed by someone calling himself (or herself) Satoshi Nakamoto. The protocol was introduced in 2008 after the publication of a white paper<ref name="BTC" /> describing the algorithm and the mechanisms for generation and distribution of BTC. At this point there are hundreds of cryptocurrencies in circulation according to [http://wikipedia.org Wikipedia], many of which are based on the Bitcoin blockchain, but only a few have gone into widespread use<ref>https://en.wikipedia.org/wiki/List_of_cryptocurrencies</ref>.<br />
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=== Smart Contracts ===<br />
One of the major potential functions of blockchain technology is through the creation of smart contracts. Various components of contracts, including proof of the involved parties, requirements for completion, and actions upon completion of the contract can be encoded in blocks. These can then be added to a blockchain and become available for independent verification, which can even lead to automatic processing of contracts when their requirements have been fulfilled.<br />
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Smart contracts are scripts which have various rules and logic that automatically execute when those rules are met. Smart contracts allow heavily automated workflows between transacting parties in the network while maintaining anonymity. Once the contract has been executed, one can take custody over assets or pre-defined payments can be issued. <ref>Christidis, K & Devetsikiotis, M. (2016, May 10). Blockchains and Smart Contracts for the Internet of Things. IEEE Access, 4, 2292-2303. doi: 10.1109/ACCESS.2016.2566339</ref> They are importantly different in the sense that they are stored on a distributed network and they can be verified as true without knowledge of the contract specifications <ref>https://bitsonblocks.net/2016/02/01/a-gentle-introduction-to-smart-contracts/</ref>.<br />
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[https://ethereum.org The Ethereum Project] was one of the first to introduce the concept of smart contracts using their alternative blockchain and currency token, [https://www.ethereum.org/ether ether].<br />
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=== Securities Exchanges and Finance ===<br />
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One of the hottest arenas for blockchain development currently is in the financial markets, an extension of the original cryptocurrency use cases for the blockchain. Multiple stock markets and other financial firms have initiated investigations and pilot projects into the feasibility and utility of the blockchain for contracts and tracking of financial instruments. NASDAQ has been one of the first major markets to put blockchain technology into use, and has released some information on its implementation, called Linq <ref>http://ir.nasdaq.com/releasedetail.cfm?releaseid=948326</ref><ref>http://www.coindesk.com/hands-on-with-linq-nasdaqs-private-markets-blockchain-project/</ref>. The cryptocurrency website [http://www.coindesk.com Coindesk] has also produced a list of 10 exchanges using or investigating blockchain technologies<ref>http://www.coindesk.com/10-stock-exchanges-blockchain/</ref>.<br />
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Additionally, financial firms such as Visa have been experimenting with the blockchain for keeping track of transactions as well as with proof of concept applications such as remittance<ref>http://www.coindesk.com/hands-on-with-visa-europes-bitcoin-remittance-app/</ref>.<br />
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== Advantages and Disadvantages of Blockchain ==<br />
<br />
Blockchain is a novel concept and is being explored in various sectors. While there may be several applications and limitations of this technology in future, some of them are highlighted below<ref>Fauvel, W. (2017, August 11). Blockchain Advantage and Disadvantages. Medium. Retrieved from: https://medium.com/nudjed/blockchain-advantage-and-disadvantages-e76dfde3bbc0</ref>:<br />
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=== Pros: ===<br />
# Distributed: There is no single owner of the database. As anyone can contribute and be a part of the network, the risks of data tampering and fraud are minimal. As Nakamoto <ref name="BTC" /> mentioned, as long as the majority of nodes are honest, a random attacker would not be able to alter the history.<br />
# Trustless: As every node in the network will have a copy of the blockchain and they verify the transactions independently. Hence, this system allows transaction even if the parties don't trust each other.<br />
# Immutable: Once the transaction is verified and embedded in the blockchain, it is almost impossible to undo it, and the complexity increases with time as more blocks are added downstream. This allows keeping a track of accurate events that occurred through the history.<br />
# Decentralized: There is no middleman like banks or data owners. This helps avoid manipulation of the market by the owners.<br />
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=== Cons: ===<br />
# Waste of resources: As several nodes are running and utilizing a huge amount of computing power and electricity to verify and maintain the blockchain, there is more than required redundancy. <br />
# Higher cost for less value: With time, the use of network increases and the complexity of the hashing algorithm also increases. Hence, more resources are required for the same amount of work. This increases the cost of work and transactions gets slower, as miners prioritize the transactions with higher incentives causing a backlog the transactions with smaller values. <br />
# Difficulty to keep up with the size of the block: As the size continues to grow along with the complexity to solve the calculation, new nodes with smaller computing power will have difficulty joining the network and likewise, the older and slower nodes will gradually fade with decreasing incentive for the work. Hence, like Darwin’s theory of the "survival of the fittest", a few larger nodes will dominate the network creating more and more centralization of the system. <br />
# Speculative market: Due to the lack of proper regulation of this system, the market is subject to a great volatility and thus making it risky for investors. <br />
# Immutable smart contracts: As there are clear advantages of having permanent and immutable records, at the same time, there is a bitter flipside to this. For example, if there is a flaw with code that can compromise the system, it is also irreparable and creates the opportunity for the attackers to exploit the same flaw repetitively in future. As time progresses, the capability of repairing the error will be even more complex.<br />
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=== Possible Solutions: ===<br />
* The issues with resource wastefulness and diminishing return of investment are mainly an issue with Proof-of-Work Systems, and can be improved with new blockchain innovations such as [https://en.bitcoin.it/wiki/Proof_of_Stake Proof of Stake (Bitcoin Wiki)] or blockchain scaling<ref>Croman, Kyle, et al. "On scaling decentralized blockchains." International Conference on Financial Cryptography and Data Security. Springer, Berlin, Heidelberg, 2016.</ref><br />
** There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake<ref>Siim, Janno. "Proof-of-Stake."</ref>. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker.<br />
** Currently, all computers that participate in mining a blockchain process every transaction. This is very slow and resource wasteful. A solution to this is to calculate how many computers will be needed to validate a new block, and give the task of verifying a transaction to those computers. This will allow parallel processing (scaling) of "blocks" and speed up transactions. At this point, the details behind how to manage this division of tasks without compromising security still being worked out.<br />
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== Potential Use Cases in Healthcare ==<br />
Though there has yet to be a breakthrough report or use-case for blockchain technology in healthcare, there are many potential ways that the blockchain could be implemented within the current healthcare structure. Any list will likely be incomplete, but these examples represent some of the published and available literature on blockchain implementations in health.<br />
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=== Health Information Exchange (HIE) ===<br />
One major area that blockchains may be able to facilitate is the secure access to and communication of patient health records between individuals and institutions. There have been multiple white papers published on the topic, including groups from the Mayo Clinic <ref>Peterson K, Deeduvanu R, Kanjamala P, Boles K. A Blockchain-Based Approach to Health Information Exchange Networks. (1):1–10.</ref> and MIT <ref>Ekblaw A, Azaria A, Halamka JD, Lippman A, Original I, Vieira T. A Case Study for Blockchain in Healthcare: “ MedRec ” prototype for electronic health records and medical research data MedRec: Using Blockchain for Medical Data Access and Permission Management [Internet]. 2016. Available from: https://www.healthit.gov/sites/default/files/5-56-onc_blockchainchallenge_mitwhitepaper.pdf</ref> who described a system for patient information exchange based on blockchain technology that would allow patient-controlled access to records across institutions using HL7 Fast Healthcare Interoperability Resources ([[FHIR]]), [http://json.org JSON], or other encoding system. In these models the actual health care data are not encoded in the blockchain, but are merely references pointing to where the data reside, such as at institutions or in a "data lake" <ref>Linn LA, Koo MB. Blockchain For Health Data and Its Potential Use in Health IT and Health Care Related Research. 2014;1–10.</ref>. Similarly, a group out of China described an app called Healthcare Data Gateway (HGD) that allows patients to view and directly control rule-based access to their health records with a smart phone interface and authentication provided by a blockchain network <ref>Yue X, Wang H, Jin D, Li M, Jiang W. Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst [Internet]. 2016 Oct;40(10):218. Available from: http://dx.doi.org/10.1007/s10916-016-0574-6</ref>. These ideas support the concept of patient-owned medical data, and would have the effect of decentralization of medical records in ways that are as yet undetermined.<br />
<br />
=== Health Research Integrity ===<br />
Academic research is a major driver of advances in health care, but in the setting of limited funding and publication pressures on researchers significant concerns have been raised regarding research integrity<ref>Titus SL, Wells J a, Rhoades LJ. Repairing research integrity. Nature [Internet]. 2008 Jun 19;453(7198):980–2. Available from: http://www.ncbi.nlm.nih.gov/pubmed/18563131</ref>. Organizations such as [http://clinicaltrials.gov ClinicalTrials.gov] and others have been developed to help drive researchers to define endpoints and analysis prior to conducting clinical trials and other studies. As it represents an immutable, verifiable record of events and transactions, the blockchain has been proposed as a potential decentralized resources for helping to ensure biomedical research integrity. Benjamin Carlisle<ref>Carlisle BG. Proof of prespecified endpoints in medical research with the bitcoin blockchain [Internet]. 2014. Available from: http://www.bgcarlisle.com/blog/2014/08/25/proof-of-prespecified-endpoints-in-medical-research-with-the-bitcoin-blockchain/</ref>, followed by several researchers from the UK<ref>Irving G, Holden J. How blockchain-timestamped protocols could improve the trustworthiness of medical science. F1000Research [Internet]. 2016;5:222. Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4866630/</ref>, proposed in 2014 that researchers could use the blockchain to record pre-specified aspects of their projects, including the study design, analysis plan, and data structure, among others, which could later be verified by consumers of the literature to decrease bias that may be introduced in post-hoc analysis<ref>Slade E, Drysdale H, Goldacre B, COMPare Team. Discrepancies Between Prespecified and Reported Outcomes. Ann Intern Med [Internet]. 2016 Mar 1;164(5):374. Available from: http://www.ncbi.nlm.nih.gov/pubmed/26720309</ref>. The blockchain also offers the potential ability to verify the integrity of actual research data and analysis by outside observers, even if the data themselves are not made publicly available. These types of implementations may lead to improvements in both the integrity of biomedical research as well as bolster public trust in medical research.<br />
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=== Personal Health Records ===<br />
This concept dovetails with the idea of HIE using the blockchain, but focuses more on the secure maintenance of a personal health record (PHR) by patients. No production PHR has been released based on this technology, but concepts such as MedVault <ref>Baxendale G. Can Blockchain Revolutionise EPRs? [Internet]. Vol. 58, ITNOW. 2016. p. 38–9. Available from: http://itnow.oxfordjournals.org/lookup/doi/10.1093/itnow/bww017</ref> use alternative blockchains such as [http://www.Colu.com Colu] to store patient data directly on the blockchain. Others such as [https://devpost.com/software/ehealthwallet eHealthWallet] have also developed prototype PHRs based on the blockchain. Patients could then share or authorize doctors and other health entities to access and modify their data.<br />
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The majority of the proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference<ref>Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230</ref><ref>Yue, X., Wang, H., Jin, D., Li, M., & Jiang, W. (2016). Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst, 40(10), 218. doi:10.1007/s10916-016-0574-6</ref>. <br />
* In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care.<br />
* As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed.<br />
* A blockchain-enabled smart contracts controlled by the patient can be used to authorize direct sharing of medical record between institutions. Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
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Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability<ref>Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230</ref>: <br />
* Digital access rules: The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application<br />
* Data aggregation: Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health<br />
* Data liquidity: Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc.<br />
* Patient identity: Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems<br />
* Data immutability: Since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time.<br />
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There are several limitations of the current state of technologies for blockchain-based personal health records:<br />
* The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. Proposed solutions include:<br />
** Validate data using a different approach to consensus such as proof-of-stake. <br />
** Store a summary of, instead of a complete clinical report.<br />
** Patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
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* A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A few solutions to this problem has been proposed:<br />
** Use permissioned (member-only) blockchain to avoid public exposure.<br />
** Basic demographic information stored on a block chain can also be encrypted to prevent access.<br />
** Store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
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* Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. <br />
** Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. <br />
** Patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
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* The largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. To overcome this, a few proposals have been made:<br />
** Expand federal incentives to patient-controlled medical record.<br />
** Researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
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=== Storage of Health Care Data ===<br />
Most of the previous examples use the blockchain not as a direct data storage medium, but instead as a secure reference point for identities, access, and data locations. At least one group from a company called Tierion, which partners with the [http://www.2.forms.healthcare.philips.com/blockchainlabs Philips Blockchain Lab ], has produced a concept called Chainpoint<ref>Vaughan AW, Bukowski J, Wilkinson S, Sporny CM, Shea R, Allen C, et al. Chainpoint: A scalable protocol for anchoring data in the blockchain and generating blockchain receipts [Internet]. 2016. Available from: https://tierion.com/chainpoint</ref>, which proposes to use a [https://proofofexistence.com/about Proof of Existence] concept and Merkle Roots<ref>Merkle RC. PROTOCOLS FOR PUBUC KEY CRYPTOSYSTEMS. In: IEEE Symposium on Security and Privacy [Internet]. 1980. p. 122–34. Available from: http://www.merkle.com/papers/Protocols.pdf</ref> to efficiently store actual patient records on the blockchain without imposing excessive transaction demands on the system.<br />
<br />
=== Billing and Claims Adjudication ===<br />
Blockchain system can help reduce administrative costs and time while automating claims adjudication and payment processing using smart contracts. For example - a smart contract is set up between payer or insurance company, provider, and patient such that when the patient sees a provider, or if a procedure is done, an entry is recorded in the blockchain. Based on the criteria set, the contract can automatically issue reimbursement from the payer as well as co-pay from the patient without having to wait for the insurance approval.<ref>Srinivasan, P. (2017, November 9). Healthcare Blockchain: How Smart Contracts Could Revolutionize Care Delivery. Prolifics. Retrieved from: https://www.prolifics.com/blog/healthcare-blockchain-how-smart-contracts-could-revolutionize-care-delivery</ref><br />
<br />
=== Drug Supply Chain and Prescription Management ===<br />
Counterfeit drugs are a major problem especially in the developing country where it is estimated that about 1 in 10 medical products are counterfeit <ref>WHO. (2017, November 28). 1 in 10 medical products in developing countries is substandard or falsified. Retrieved from: http://www.who.int/en/news-room/detail/28-11-2017-1-in-10-medical-products-in-developing-countries-is-substandard-or-falsified</ref>. Ensuring the integrity of the drug and maintaining a robust audit trail is a must to ensure patient safety. Similarly, this platform can be used in prescription drug management and track history and authenticate prescriptions using smart-contracts. <br />
<br />
=== Few Examples of Current Use Cases and Future Development ===<br />
<br />
* MedRec- it is based on Ethereum platform and focuses on medical data management using smart contracts like managing permissions and authentication processes, data sharing in an interoperable environment between healthcare systems and maintaining an audit log. <ref>Azaria, A., Ekblaw, A., Vieira, T., & Lippman, A. (2016, August 22-24). MedRec: Using Blockchain for Medical Data Access and Permission Management. 2016 2nd International Conference on Open and Big Data (OBD). doi:10.1109/obd.2016.11</ref><br />
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* Guardtime- also focuses on medical data management and has partnered with e-Health authority of Estonia to secure the country's database of health records <ref>Ruubel M. (2016, February 12). Estonian eHealth Authority Partners with Guardtime to Accelerate Transparency and Auditability in Health Care. Retrieved from: https://guardtime.com/blog/estonian-ehealth-partners-guardtime-blockchain-based-transparency</ref>. Also, recently, MyPCR smartphone platform from Guardtime has partnered with Instant Access Medical and Healthcare Gateway in the UK for patient health data management and verification of medication adherence. <ref>Ruubel M. (2018, June 20). World’s first blockchain-supported Personal Care Record Platform launched by Guardtime and partners to up to 30 million NHS patients in the UK. Retrieved from: https://guardtime.com/blog/world-s-first-blockchain-supported-personal-care-record-platform-launched-by-guardtime-and-partners</ref> <br />
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* Blockchain Health- created for healthcare research data management where users can individually authorize the release of their health information to researchers as well as track the use of their data. <ref>BlockchainHealth. (2016). Blockchain for health research. Retrieved from: https://blockchainhealth.co/</ref><br />
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* BlockMedx- it is a startup company which intends to use the blockchain platform to transmit DEA controlled drug prescriptions from physicians to pharmacies and then to patients securely. <ref>BlockMedx. (2018). Retrieved from: https://blockmedx.com/en/</ref><br />
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* MediLedger- another pharmaceutical supply chain management startup company who has partnered with several drug manufacturers and aims to provide an open, secure and interoperable network. <ref>MediLedger. (2018). The MediLedger Project. Retrieved from: https://mediledger.com/</ref><br />
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* Drug and Pharmacy Verification - [https://devpost.com/software/veripharm VeriPharm] has developed a proof of concept that would help track and verify pharmaceuticals from the raw materials to the final product administered to patients.<br />
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* Appointment Scheduling on the Blockchain - [https://devpost.com/software/dhva-appointment-blocks dhva-apointment-blocks]<br />
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* Care Coordination - Projects such as [https://devpost.com/software/simplyvitahlth simplyvitahlth] are geared toward coordinating care between multiple providers and at different institutions to ensure that complex care pathways are being followed appropriately.<br />
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<br />
There are many more potential use-cases for blockchain technology within healthcare, and undoubtedly we will continue to see development in this area in coming years. In 2016, a consortium of sponsors led by [https://gem.co/ Gem] (Whitepaper)<ref>Wood C, Winton B, Carter K, Benkert S, Dodd L, Bradley J, et al. How Blockchain Technology Can Enhance Ehr Operability [Internet]. 2016. Available from: http://research.ark-invest.com/blockchain-and-healthcare</ref> held the first healthcare oriented blockchain conference, [https://godistributed.com/health Distributed: Health] in Nashville, TN. Similarly, the Office of the National Coordinator (ONC) Tech Lab had issued a Blockchain Challenge in July, 2016.<ref>https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab</ref><br />
* The list of submissions and awards can be found [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab here]<br />
<br />
As the healthcare blockchain community grows, gatherings such as these will likely increase and blockchain technologies will increasingly be introduced at major medical conferences.<br />
<br />
== References ==<br />
<references /><br />
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Submitted by Sandeep Regmi<br />
[[Category: BMI512-FALL-18]]<br />
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Submitted by Ben Orwoll<br />
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[[Category: BMI512-FALL-16]]<br />
[[Category: Reviews]]<br />
[[Category: Other Technologies]]</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/The_Blockchain_in_HealthcareThe Blockchain in Healthcare2018-10-19T03:12:54Z<p>Phamnh: /* Personal Health Records */</p>
<hr />
<div>The blockchain is an idea centered around the concept of a secure, digital ledger system that provides a system for efficient, auditable transactions of almost any type between entities <ref>Tapscott D, Tapscott A. Blockchain Revolution: How the Technology Behind Bitcoin Is Changing Money, Business, and the World. United States: Portfolio; 2016. 1-368 p.</ref>. All information related to blockchain transactions is at once both independently verifiable by all (even outside) parties as correct and also inscrutable to entities without explicit permission. The first and probably most well-known implementation of blockchain technology is [https://bitcoin.org Bitcoin] <ref name="BTC">Nakamoto S. Bitcoin: A Peer-to-Peer Electronic Cash System. WwwBitcoinOrg [Internet]. 2008;9. Available from: https://bitcoin.org/bitcoin.pdf</ref>, but there has been a massive expansion of blockchain use-cases since Bitcoin's initial introduction.<br />
<br />
<br />
<br />
== What is the Blockchain? ==<br />
<br />
First, it should be clear that there is no one blockchain to rule them all. "The Blockchain," as it is often referred, really is a concept of a series (chain) of interrelated sets (blocks) of encrypted information. Hence a chain of blocks, or blockchain. There are many such blockchains in existence, and one could choose to do transactions on any one of them or create a new blockchain.<br />
<br />
<br />
An important aspect of most blockchains is that they are designed to be maintained on a distributed network of multiple nodes. Each node holds a complete copy of the blockchain and adds each sequential new block as it is created. This system allows every transaction on the blockchain to be verified by any or all of the nodes in the network, and also makes it very difficult for the information held in the blockchain to become lost or unavailable if any one or even most of the nodes go offline.<br />
<br />
<br />
Transactions that are set to be added to the blockchain are added to the newest block as soon as it is created. This makes the continued existence of the blockchain dependent on the creation of new blocks. There are several main methods for the creation of new blocks on the network, and the choice of method depends somewhat on the purpose of the blockchain in question. Bitcoin, the first cryptocurrency, uses a method called [https://en.wikipedia.org/wiki/Proof-of-work_system Proof of Work System (Wikipedia)]:<br />
* In the traditional Proof of Work System, each block validator, or "miner," competes to validate the block by processing a task. The winner is the first person to complete this task. The chance of completion of the task is random based on a hash function, but increases with the more "work" a person puts into the task. The system can automatically vary the difficulty of the task to limit the speed of block generation. The winner is credited for his/her work by a small amount of currency. <br />
<br />
<br />
The blockchain has moved beyond simply processing transactions of cryptocurrency such as Bitcoin. Any data that can be encoded into a cryptographic [https://en.wikipedia.org/wiki/Hash_function hash] can be added to a blockchain. Various different ideas have been proposed, and I will not attempt to list them here, but they are wide ranging. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0<ref>Swan, M. (2015). Blockchain: Blueprint for a new economy: " O'Reilly Media, Inc."</ref>. Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education.<br />
<br />
<br />
=== Blockchain Development Groups ===<br />
Certainly a non-exhaustive list . . .<br />
<br />
* [https://bitcoin.org/en/ Bitcoin]<br />
<br />
* [https://hyperledger.org The Hyperledger Project]<br />
<br />
* [https://ethereum.org The Ethereum Project]<br />
<br />
* [https://r3cev.com/blog/2016/4/4/introducing-r3-corda-a-distributed-ledger-designed-for-financial-services The CORDA Platform]<br />
<br />
* [http://www.muskokagroup.org/ The Muskoka Group]<br />
<br />
* [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab The ONC Tech Lab]<br />
<br />
== Blockchain Use Cases ==<br />
<br />
=== Cryptocurrency ===<br />
Bitcoin (BTC) was the first cryptocurrency based on the blockchain and was developed by someone calling himself (or herself) Satoshi Nakamoto. The protocol was introduced in 2008 after the publication of a white paper<ref name="BTC" /> describing the algorithm and the mechanisms for generation and distribution of BTC. At this point there are hundreds of cryptocurrencies in circulation according to [http://wikipedia.org Wikipedia], many of which are based on the Bitcoin blockchain, but only a few have gone into widespread use<ref>https://en.wikipedia.org/wiki/List_of_cryptocurrencies</ref>.<br />
<br />
=== Smart Contracts ===<br />
One of the major potential functions of blockchain technology is through the creation of smart contracts. Various components of contracts, including proof of the involved parties, requirements for completion, and actions upon completion of the contract can be encoded in blocks. These can then be added to a blockchain and become available for independent verification, which can even lead to automatic processing of contracts when their requirements have been fulfilled.<br />
<br />
Smart contracts are scripts which have various rules and logic that automatically execute when those rules are met. Smart contracts allow heavily automated workflows between transacting parties in the network while maintaining anonymity. Once the contract has been executed, one can take custody over assets or pre-defined payments can be issued. <ref>Christidis, K & Devetsikiotis, M. (2016, May 10). Blockchains and Smart Contracts for the Internet of Things. IEEE Access, 4, 2292-2303. doi: 10.1109/ACCESS.2016.2566339</ref> They are importantly different in the sense that they are stored on a distributed network and they can be verified as true without knowledge of the contract specifications <ref>https://bitsonblocks.net/2016/02/01/a-gentle-introduction-to-smart-contracts/</ref>.<br />
<br />
[https://ethereum.org The Ethereum Project] was one of the first to introduce the concept of smart contracts using their alternative blockchain and currency token, [https://www.ethereum.org/ether ether].<br />
<br />
=== Securities Exchanges and Finance ===<br />
<br />
One of the hottest arenas for blockchain development currently is in the financial markets, an extension of the original cryptocurrency use cases for the blockchain. Multiple stock markets and other financial firms have initiated investigations and pilot projects into the feasibility and utility of the blockchain for contracts and tracking of financial instruments. NASDAQ has been one of the first major markets to put blockchain technology into use, and has released some information on its implementation, called Linq <ref>http://ir.nasdaq.com/releasedetail.cfm?releaseid=948326</ref><ref>http://www.coindesk.com/hands-on-with-linq-nasdaqs-private-markets-blockchain-project/</ref>. The cryptocurrency website [http://www.coindesk.com Coindesk] has also produced a list of 10 exchanges using or investigating blockchain technologies<ref>http://www.coindesk.com/10-stock-exchanges-blockchain/</ref>.<br />
<br />
<br />
Additionally, financial firms such as Visa have been experimenting with the blockchain for keeping track of transactions as well as with proof of concept applications such as remittance<ref>http://www.coindesk.com/hands-on-with-visa-europes-bitcoin-remittance-app/</ref>.<br />
<br />
== Advantages and Disadvantages of Blockchain ==<br />
<br />
Blockchain is a novel concept and is being explored in various sectors. While there may be several applications and limitations of this technology in future, some of them are highlighted below<ref>Fauvel, W. (2017, August 11). Blockchain Advantage and Disadvantages. Medium. Retrieved from: https://medium.com/nudjed/blockchain-advantage-and-disadvantages-e76dfde3bbc0</ref>:<br />
<br />
=== Pros: ===<br />
# Distributed: There is no single owner of the database. As anyone can contribute and be a part of the network, the risks of data tampering and fraud are minimal. As Nakamoto <ref name="BTC" /> mentioned, as long as the majority of nodes are honest, a random attacker would not be able to alter the history.<br />
# Trustless: As every node in the network will have a copy of the blockchain and they verify the transactions independently. Hence, this system allows transaction even if the parties don't trust each other.<br />
# Immutable: Once the transaction is verified and embedded in the blockchain, it is almost impossible to undo it, and the complexity increases with time as more blocks are added downstream. This allows keeping a track of accurate events that occurred through the history.<br />
# Decentralized: There is no middleman like banks or data owners. This helps avoid manipulation of the market by the owners.<br />
<br />
<br />
=== Cons: ===<br />
# Waste of resources: As several nodes are running and utilizing a huge amount of computing power and electricity to verify and maintain the blockchain, there is more than required redundancy. <br />
# Higher cost for less value: With time, the use of network increases and the complexity of the hashing algorithm also increases. Hence, more resources are required for the same amount of work. This increases the cost of work and transactions gets slower, as miners prioritize the transactions with higher incentives causing a backlog the transactions with smaller values. <br />
# Difficulty to keep up with the size of the block: As the size continues to grow along with the complexity to solve the calculation, new nodes with smaller computing power will have difficulty joining the network and likewise, the older and slower nodes will gradually fade with decreasing incentive for the work. Hence, like Darwin’s theory of the "survival of the fittest", a few larger nodes will dominate the network creating more and more centralization of the system. <br />
# Speculative market: Due to the lack of proper regulation of this system, the market is subject to a great volatility and thus making it risky for investors. <br />
# Immutable smart contracts: As there are clear advantages of having permanent and immutable records, at the same time, there is a bitter flipside to this. For example, if there is a flaw with code that can compromise the system, it is also irreparable and creates the opportunity for the attackers to exploit the same flaw repetitively in future. As time progresses, the capability of repairing the error will be even more complex.<br />
<br />
<br />
<br />
=== Possible Solutions: ===<br />
* The issues with resource wastefulness and diminishing return of investment are mainly an issue with Proof-of-Work Systems, and can be improved with new blockchain innovations such as [https://en.bitcoin.it/wiki/Proof_of_Stake Proof of Stake (Bitcoin Wiki)] or blockchain scaling<ref>Croman, Kyle, et al. "On scaling decentralized blockchains." International Conference on Financial Cryptography and Data Security. Springer, Berlin, Heidelberg, 2016.</ref><br />
** There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake<ref>Siim, Janno. "Proof-of-Stake."</ref>. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker.<br />
** Currently, all computers that participate in mining a blockchain process every transaction. This is very slow and resource wasteful. A solution to this is to calculate how many computers will be needed to validate a new block, and give the task of verifying a transaction to those computers. This will allow parallel processing (scaling) of "blocks" and speed up transactions. At this point, the details behind how to manage this division of tasks without compromising security still being worked out.<br />
<br />
== Potential Use Cases in Healthcare ==<br />
Though there has yet to be a breakthrough report or use-case for blockchain technology in healthcare, there are many potential ways that the blockchain could be implemented within the current healthcare structure. Any list will likely be incomplete, but these examples represent some of the published and available literature on blockchain implementations in health.<br />
<br />
=== Health Information Exchange (HIE) ===<br />
One major area that blockchains may be able to facilitate is the secure access to and communication of patient health records between individuals and institutions. There have been multiple white papers published on the topic, including groups from the Mayo Clinic <ref>Peterson K, Deeduvanu R, Kanjamala P, Boles K. A Blockchain-Based Approach to Health Information Exchange Networks. (1):1–10.</ref> and MIT <ref>Ekblaw A, Azaria A, Halamka JD, Lippman A, Original I, Vieira T. A Case Study for Blockchain in Healthcare: “ MedRec ” prototype for electronic health records and medical research data MedRec: Using Blockchain for Medical Data Access and Permission Management [Internet]. 2016. Available from: https://www.healthit.gov/sites/default/files/5-56-onc_blockchainchallenge_mitwhitepaper.pdf</ref> who described a system for patient information exchange based on blockchain technology that would allow patient-controlled access to records across institutions using HL7 Fast Healthcare Interoperability Resources ([[FHIR]]), [http://json.org JSON], or other encoding system. In these models the actual health care data are not encoded in the blockchain, but are merely references pointing to where the data reside, such as at institutions or in a "data lake" <ref>Linn LA, Koo MB. Blockchain For Health Data and Its Potential Use in Health IT and Health Care Related Research. 2014;1–10.</ref>. Similarly, a group out of China described an app called Healthcare Data Gateway (HGD) that allows patients to view and directly control rule-based access to their health records with a smart phone interface and authentication provided by a blockchain network <ref>Yue X, Wang H, Jin D, Li M, Jiang W. Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst [Internet]. 2016 Oct;40(10):218. Available from: http://dx.doi.org/10.1007/s10916-016-0574-6</ref>. These ideas support the concept of patient-owned medical data, and would have the effect of decentralization of medical records in ways that are as yet undetermined.<br />
<br />
=== Health Research Integrity ===<br />
Academic research is a major driver of advances in health care, but in the setting of limited funding and publication pressures on researchers significant concerns have been raised regarding research integrity<ref>Titus SL, Wells J a, Rhoades LJ. Repairing research integrity. Nature [Internet]. 2008 Jun 19;453(7198):980–2. Available from: http://www.ncbi.nlm.nih.gov/pubmed/18563131</ref>. Organizations such as [http://clinicaltrials.gov ClinicalTrials.gov] and others have been developed to help drive researchers to define endpoints and analysis prior to conducting clinical trials and other studies. As it represents an immutable, verifiable record of events and transactions, the blockchain has been proposed as a potential decentralized resources for helping to ensure biomedical research integrity. Benjamin Carlisle<ref>Carlisle BG. Proof of prespecified endpoints in medical research with the bitcoin blockchain [Internet]. 2014. Available from: http://www.bgcarlisle.com/blog/2014/08/25/proof-of-prespecified-endpoints-in-medical-research-with-the-bitcoin-blockchain/</ref>, followed by several researchers from the UK<ref>Irving G, Holden J. How blockchain-timestamped protocols could improve the trustworthiness of medical science. F1000Research [Internet]. 2016;5:222. Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4866630/</ref>, proposed in 2014 that researchers could use the blockchain to record pre-specified aspects of their projects, including the study design, analysis plan, and data structure, among others, which could later be verified by consumers of the literature to decrease bias that may be introduced in post-hoc analysis<ref>Slade E, Drysdale H, Goldacre B, COMPare Team. Discrepancies Between Prespecified and Reported Outcomes. Ann Intern Med [Internet]. 2016 Mar 1;164(5):374. Available from: http://www.ncbi.nlm.nih.gov/pubmed/26720309</ref>. The blockchain also offers the potential ability to verify the integrity of actual research data and analysis by outside observers, even if the data themselves are not made publicly available. These types of implementations may lead to improvements in both the integrity of biomedical research as well as bolster public trust in medical research.<br />
<br />
=== Personal Health Records ===<br />
This concept dovetails with the idea of HIE using the blockchain, but focuses more on the secure maintenance of a personal health record (PHR) by patients. No production PHR has been released based on this technology, but concepts such as MedVault <ref>Baxendale G. Can Blockchain Revolutionise EPRs? [Internet]. Vol. 58, ITNOW. 2016. p. 38–9. Available from: http://itnow.oxfordjournals.org/lookup/doi/10.1093/itnow/bww017</ref> use alternative blockchains such as [http://www.Colu.com Colu] to store patient data directly on the blockchain. Others such as [https://devpost.com/software/ehealthwallet eHealthWallet] have also developed prototype PHRs based on the blockchain. Patients could then share or authorize doctors and other health entities to access and modify their data.<br />
<br />
The majority of the proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference<ref>Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230</ref><ref>Yue, X., Wang, H., Jin, D., Li, M., & Jiang, W. (2016). Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst, 40(10), 218. doi:10.1007/s10916-016-0574-6</ref>. <br />
* In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care.<br />
* As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed.<br />
* A blockchain-enabled smart contracts controlled by the patient can be used to authorize direct sharing of medical record between institutions. Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability<ref>Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230</ref>: <br />
* Digital access rules: The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application<br />
* Data aggregation: Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health<br />
* Data liquidity: Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc.<br />
* Patient identity: Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems<br />
* Data immutability: Since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time.<br />
<br />
There are several limitations of the current state of technologies for blockchain-based personal health records:<br />
* The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. Proposed solutions include:<br />
** Validate data using a different approach to consensus such as proof-of-stake[3]. <br />
** Store a summary of, instead of a complete clinical report [6].<br />
** Patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
* A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A few solutions to this problem has been proposed:<br />
** Use permissioned (member-only) blockchain to avoid public exposure.<br />
** Basic demographic information stored on a block chain can also be encrypted to prevent access.<br />
** Store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
* Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. <br />
** Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. <br />
** Patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
* The largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. To overcome this, a few proposals have been made:<br />
** Expand federal incentives to patient-controlled medical record.<br />
** Researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
=== Storage of Health Care Data ===<br />
Most of the previous examples use the blockchain not as a direct data storage medium, but instead as a secure reference point for identities, access, and data locations. At least one group from a company called Tierion, which partners with the [http://www.2.forms.healthcare.philips.com/blockchainlabs Philips Blockchain Lab ], has produced a concept called Chainpoint<ref>Vaughan AW, Bukowski J, Wilkinson S, Sporny CM, Shea R, Allen C, et al. Chainpoint: A scalable protocol for anchoring data in the blockchain and generating blockchain receipts [Internet]. 2016. Available from: https://tierion.com/chainpoint</ref>, which proposes to use a [https://proofofexistence.com/about Proof of Existence] concept and Merkle Roots<ref>Merkle RC. PROTOCOLS FOR PUBUC KEY CRYPTOSYSTEMS. In: IEEE Symposium on Security and Privacy [Internet]. 1980. p. 122–34. Available from: http://www.merkle.com/papers/Protocols.pdf</ref> to efficiently store actual patient records on the blockchain without imposing excessive transaction demands on the system.<br />
<br />
=== Billing and Claims Adjudication ===<br />
Blockchain system can help reduce administrative costs and time while automating claims adjudication and payment processing using smart contracts. For example - a smart contract is set up between payer or insurance company, provider, and patient such that when the patient sees a provider, or if a procedure is done, an entry is recorded in the blockchain. Based on the criteria set, the contract can automatically issue reimbursement from the payer as well as co-pay from the patient without having to wait for the insurance approval.<ref>Srinivasan, P. (2017, November 9). Healthcare Blockchain: How Smart Contracts Could Revolutionize Care Delivery. Prolifics. Retrieved from: https://www.prolifics.com/blog/healthcare-blockchain-how-smart-contracts-could-revolutionize-care-delivery</ref><br />
<br />
=== Drug Supply Chain and Prescription Management ===<br />
Counterfeit drugs are a major problem especially in the developing country where it is estimated that about 1 in 10 medical products are counterfeit <ref>WHO. (2017, November 28). 1 in 10 medical products in developing countries is substandard or falsified. Retrieved from: http://www.who.int/en/news-room/detail/28-11-2017-1-in-10-medical-products-in-developing-countries-is-substandard-or-falsified</ref>. Ensuring the integrity of the drug and maintaining a robust audit trail is a must to ensure patient safety. Similarly, this platform can be used in prescription drug management and track history and authenticate prescriptions using smart-contracts. <br />
<br />
=== Few Examples of Current Use Cases and Future Development ===<br />
<br />
* MedRec- it is based on Ethereum platform and focuses on medical data management using smart contracts like managing permissions and authentication processes, data sharing in an interoperable environment between healthcare systems and maintaining an audit log. <ref>Azaria, A., Ekblaw, A., Vieira, T., & Lippman, A. (2016, August 22-24). MedRec: Using Blockchain for Medical Data Access and Permission Management. 2016 2nd International Conference on Open and Big Data (OBD). doi:10.1109/obd.2016.11</ref><br />
<br />
* Guardtime- also focuses on medical data management and has partnered with e-Health authority of Estonia to secure the country's database of health records <ref>Ruubel M. (2016, February 12). Estonian eHealth Authority Partners with Guardtime to Accelerate Transparency and Auditability in Health Care. Retrieved from: https://guardtime.com/blog/estonian-ehealth-partners-guardtime-blockchain-based-transparency</ref>. Also, recently, MyPCR smartphone platform from Guardtime has partnered with Instant Access Medical and Healthcare Gateway in the UK for patient health data management and verification of medication adherence. <ref>Ruubel M. (2018, June 20). World’s first blockchain-supported Personal Care Record Platform launched by Guardtime and partners to up to 30 million NHS patients in the UK. Retrieved from: https://guardtime.com/blog/world-s-first-blockchain-supported-personal-care-record-platform-launched-by-guardtime-and-partners</ref> <br />
<br />
* Blockchain Health- created for healthcare research data management where users can individually authorize the release of their health information to researchers as well as track the use of their data. <ref>BlockchainHealth. (2016). Blockchain for health research. Retrieved from: https://blockchainhealth.co/</ref><br />
<br />
* BlockMedx- it is a startup company which intends to use the blockchain platform to transmit DEA controlled drug prescriptions from physicians to pharmacies and then to patients securely. <ref>BlockMedx. (2018). Retrieved from: https://blockmedx.com/en/</ref><br />
<br />
* MediLedger- another pharmaceutical supply chain management startup company who has partnered with several drug manufacturers and aims to provide an open, secure and interoperable network. <ref>MediLedger. (2018). The MediLedger Project. Retrieved from: https://mediledger.com/</ref><br />
<br />
* Drug and Pharmacy Verification - [https://devpost.com/software/veripharm VeriPharm] has developed a proof of concept that would help track and verify pharmaceuticals from the raw materials to the final product administered to patients.<br />
<br />
* Appointment Scheduling on the Blockchain - [https://devpost.com/software/dhva-appointment-blocks dhva-apointment-blocks]<br />
<br />
* Care Coordination - Projects such as [https://devpost.com/software/simplyvitahlth simplyvitahlth] are geared toward coordinating care between multiple providers and at different institutions to ensure that complex care pathways are being followed appropriately.<br />
<br />
<br />
There are many more potential use-cases for blockchain technology within healthcare, and undoubtedly we will continue to see development in this area in coming years. In 2016, a consortium of sponsors led by [https://gem.co/ Gem] (Whitepaper)<ref>Wood C, Winton B, Carter K, Benkert S, Dodd L, Bradley J, et al. How Blockchain Technology Can Enhance Ehr Operability [Internet]. 2016. Available from: http://research.ark-invest.com/blockchain-and-healthcare</ref> held the first healthcare oriented blockchain conference, [https://godistributed.com/health Distributed: Health] in Nashville, TN. Similarly, the Office of the National Coordinator (ONC) Tech Lab had issued a Blockchain Challenge in July, 2016.<ref>https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab</ref><br />
* The list of submissions and awards can be found [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab here]<br />
<br />
As the healthcare blockchain community grows, gatherings such as these will likely increase and blockchain technologies will increasingly be introduced at major medical conferences.<br />
<br />
== References ==<br />
<references /><br />
<br />
Submitted by Sandeep Regmi<br />
[[Category: BMI512-FALL-18]]<br />
<br />
Submitted by Ben Orwoll<br />
<br />
[[Category: BMI512-FALL-16]]<br />
[[Category: Reviews]]<br />
[[Category: Other Technologies]]</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/The_Blockchain_in_HealthcareThe Blockchain in Healthcare2018-10-19T03:09:55Z<p>Phamnh: /* Possible Solutions: */</p>
<hr />
<div>The blockchain is an idea centered around the concept of a secure, digital ledger system that provides a system for efficient, auditable transactions of almost any type between entities <ref>Tapscott D, Tapscott A. Blockchain Revolution: How the Technology Behind Bitcoin Is Changing Money, Business, and the World. United States: Portfolio; 2016. 1-368 p.</ref>. All information related to blockchain transactions is at once both independently verifiable by all (even outside) parties as correct and also inscrutable to entities without explicit permission. The first and probably most well-known implementation of blockchain technology is [https://bitcoin.org Bitcoin] <ref name="BTC">Nakamoto S. Bitcoin: A Peer-to-Peer Electronic Cash System. WwwBitcoinOrg [Internet]. 2008;9. Available from: https://bitcoin.org/bitcoin.pdf</ref>, but there has been a massive expansion of blockchain use-cases since Bitcoin's initial introduction.<br />
<br />
<br />
<br />
== What is the Blockchain? ==<br />
<br />
First, it should be clear that there is no one blockchain to rule them all. "The Blockchain," as it is often referred, really is a concept of a series (chain) of interrelated sets (blocks) of encrypted information. Hence a chain of blocks, or blockchain. There are many such blockchains in existence, and one could choose to do transactions on any one of them or create a new blockchain.<br />
<br />
<br />
An important aspect of most blockchains is that they are designed to be maintained on a distributed network of multiple nodes. Each node holds a complete copy of the blockchain and adds each sequential new block as it is created. This system allows every transaction on the blockchain to be verified by any or all of the nodes in the network, and also makes it very difficult for the information held in the blockchain to become lost or unavailable if any one or even most of the nodes go offline.<br />
<br />
<br />
Transactions that are set to be added to the blockchain are added to the newest block as soon as it is created. This makes the continued existence of the blockchain dependent on the creation of new blocks. There are several main methods for the creation of new blocks on the network, and the choice of method depends somewhat on the purpose of the blockchain in question. Bitcoin, the first cryptocurrency, uses a method called [https://en.wikipedia.org/wiki/Proof-of-work_system Proof of Work System (Wikipedia)]:<br />
* In the traditional Proof of Work System, each block validator, or "miner," competes to validate the block by processing a task. The winner is the first person to complete this task. The chance of completion of the task is random based on a hash function, but increases with the more "work" a person puts into the task. The system can automatically vary the difficulty of the task to limit the speed of block generation. The winner is credited for his/her work by a small amount of currency. <br />
<br />
<br />
The blockchain has moved beyond simply processing transactions of cryptocurrency such as Bitcoin. Any data that can be encoded into a cryptographic [https://en.wikipedia.org/wiki/Hash_function hash] can be added to a blockchain. Various different ideas have been proposed, and I will not attempt to list them here, but they are wide ranging. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0<ref>Swan, M. (2015). Blockchain: Blueprint for a new economy: " O'Reilly Media, Inc."</ref>. Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education.<br />
<br />
<br />
=== Blockchain Development Groups ===<br />
Certainly a non-exhaustive list . . .<br />
<br />
* [https://bitcoin.org/en/ Bitcoin]<br />
<br />
* [https://hyperledger.org The Hyperledger Project]<br />
<br />
* [https://ethereum.org The Ethereum Project]<br />
<br />
* [https://r3cev.com/blog/2016/4/4/introducing-r3-corda-a-distributed-ledger-designed-for-financial-services The CORDA Platform]<br />
<br />
* [http://www.muskokagroup.org/ The Muskoka Group]<br />
<br />
* [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab The ONC Tech Lab]<br />
<br />
== Blockchain Use Cases ==<br />
<br />
=== Cryptocurrency ===<br />
Bitcoin (BTC) was the first cryptocurrency based on the blockchain and was developed by someone calling himself (or herself) Satoshi Nakamoto. The protocol was introduced in 2008 after the publication of a white paper<ref name="BTC" /> describing the algorithm and the mechanisms for generation and distribution of BTC. At this point there are hundreds of cryptocurrencies in circulation according to [http://wikipedia.org Wikipedia], many of which are based on the Bitcoin blockchain, but only a few have gone into widespread use<ref>https://en.wikipedia.org/wiki/List_of_cryptocurrencies</ref>.<br />
<br />
=== Smart Contracts ===<br />
One of the major potential functions of blockchain technology is through the creation of smart contracts. Various components of contracts, including proof of the involved parties, requirements for completion, and actions upon completion of the contract can be encoded in blocks. These can then be added to a blockchain and become available for independent verification, which can even lead to automatic processing of contracts when their requirements have been fulfilled.<br />
<br />
Smart contracts are scripts which have various rules and logic that automatically execute when those rules are met. Smart contracts allow heavily automated workflows between transacting parties in the network while maintaining anonymity. Once the contract has been executed, one can take custody over assets or pre-defined payments can be issued. <ref>Christidis, K & Devetsikiotis, M. (2016, May 10). Blockchains and Smart Contracts for the Internet of Things. IEEE Access, 4, 2292-2303. doi: 10.1109/ACCESS.2016.2566339</ref> They are importantly different in the sense that they are stored on a distributed network and they can be verified as true without knowledge of the contract specifications <ref>https://bitsonblocks.net/2016/02/01/a-gentle-introduction-to-smart-contracts/</ref>.<br />
<br />
[https://ethereum.org The Ethereum Project] was one of the first to introduce the concept of smart contracts using their alternative blockchain and currency token, [https://www.ethereum.org/ether ether].<br />
<br />
=== Securities Exchanges and Finance ===<br />
<br />
One of the hottest arenas for blockchain development currently is in the financial markets, an extension of the original cryptocurrency use cases for the blockchain. Multiple stock markets and other financial firms have initiated investigations and pilot projects into the feasibility and utility of the blockchain for contracts and tracking of financial instruments. NASDAQ has been one of the first major markets to put blockchain technology into use, and has released some information on its implementation, called Linq <ref>http://ir.nasdaq.com/releasedetail.cfm?releaseid=948326</ref><ref>http://www.coindesk.com/hands-on-with-linq-nasdaqs-private-markets-blockchain-project/</ref>. The cryptocurrency website [http://www.coindesk.com Coindesk] has also produced a list of 10 exchanges using or investigating blockchain technologies<ref>http://www.coindesk.com/10-stock-exchanges-blockchain/</ref>.<br />
<br />
<br />
Additionally, financial firms such as Visa have been experimenting with the blockchain for keeping track of transactions as well as with proof of concept applications such as remittance<ref>http://www.coindesk.com/hands-on-with-visa-europes-bitcoin-remittance-app/</ref>.<br />
<br />
== Advantages and Disadvantages of Blockchain ==<br />
<br />
Blockchain is a novel concept and is being explored in various sectors. While there may be several applications and limitations of this technology in future, some of them are highlighted below<ref>Fauvel, W. (2017, August 11). Blockchain Advantage and Disadvantages. Medium. Retrieved from: https://medium.com/nudjed/blockchain-advantage-and-disadvantages-e76dfde3bbc0</ref>:<br />
<br />
=== Pros: ===<br />
# Distributed: There is no single owner of the database. As anyone can contribute and be a part of the network, the risks of data tampering and fraud are minimal. As Nakamoto <ref name="BTC" /> mentioned, as long as the majority of nodes are honest, a random attacker would not be able to alter the history.<br />
# Trustless: As every node in the network will have a copy of the blockchain and they verify the transactions independently. Hence, this system allows transaction even if the parties don't trust each other.<br />
# Immutable: Once the transaction is verified and embedded in the blockchain, it is almost impossible to undo it, and the complexity increases with time as more blocks are added downstream. This allows keeping a track of accurate events that occurred through the history.<br />
# Decentralized: There is no middleman like banks or data owners. This helps avoid manipulation of the market by the owners.<br />
<br />
<br />
=== Cons: ===<br />
# Waste of resources: As several nodes are running and utilizing a huge amount of computing power and electricity to verify and maintain the blockchain, there is more than required redundancy. <br />
# Higher cost for less value: With time, the use of network increases and the complexity of the hashing algorithm also increases. Hence, more resources are required for the same amount of work. This increases the cost of work and transactions gets slower, as miners prioritize the transactions with higher incentives causing a backlog the transactions with smaller values. <br />
# Difficulty to keep up with the size of the block: As the size continues to grow along with the complexity to solve the calculation, new nodes with smaller computing power will have difficulty joining the network and likewise, the older and slower nodes will gradually fade with decreasing incentive for the work. Hence, like Darwin’s theory of the "survival of the fittest", a few larger nodes will dominate the network creating more and more centralization of the system. <br />
# Speculative market: Due to the lack of proper regulation of this system, the market is subject to a great volatility and thus making it risky for investors. <br />
# Immutable smart contracts: As there are clear advantages of having permanent and immutable records, at the same time, there is a bitter flipside to this. For example, if there is a flaw with code that can compromise the system, it is also irreparable and creates the opportunity for the attackers to exploit the same flaw repetitively in future. As time progresses, the capability of repairing the error will be even more complex.<br />
<br />
<br />
<br />
=== Possible Solutions: ===<br />
* The issues with resource wastefulness and diminishing return of investment are mainly an issue with Proof-of-Work Systems, and can be improved with new blockchain innovations such as [https://en.bitcoin.it/wiki/Proof_of_Stake Proof of Stake (Bitcoin Wiki)] or blockchain scaling<ref>Croman, Kyle, et al. "On scaling decentralized blockchains." International Conference on Financial Cryptography and Data Security. Springer, Berlin, Heidelberg, 2016.</ref><br />
** There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake<ref>Siim, Janno. "Proof-of-Stake."</ref>. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker.<br />
** Currently, all computers that participate in mining a blockchain process every transaction. This is very slow and resource wasteful. A solution to this is to calculate how many computers will be needed to validate a new block, and give the task of verifying a transaction to those computers. This will allow parallel processing (scaling) of "blocks" and speed up transactions. At this point, the details behind how to manage this division of tasks without compromising security still being worked out.<br />
<br />
== Potential Use Cases in Healthcare ==<br />
Though there has yet to be a breakthrough report or use-case for blockchain technology in healthcare, there are many potential ways that the blockchain could be implemented within the current healthcare structure. Any list will likely be incomplete, but these examples represent some of the published and available literature on blockchain implementations in health.<br />
<br />
=== Health Information Exchange (HIE) ===<br />
One major area that blockchains may be able to facilitate is the secure access to and communication of patient health records between individuals and institutions. There have been multiple white papers published on the topic, including groups from the Mayo Clinic <ref>Peterson K, Deeduvanu R, Kanjamala P, Boles K. A Blockchain-Based Approach to Health Information Exchange Networks. (1):1–10.</ref> and MIT <ref>Ekblaw A, Azaria A, Halamka JD, Lippman A, Original I, Vieira T. A Case Study for Blockchain in Healthcare: “ MedRec ” prototype for electronic health records and medical research data MedRec: Using Blockchain for Medical Data Access and Permission Management [Internet]. 2016. Available from: https://www.healthit.gov/sites/default/files/5-56-onc_blockchainchallenge_mitwhitepaper.pdf</ref> who described a system for patient information exchange based on blockchain technology that would allow patient-controlled access to records across institutions using HL7 Fast Healthcare Interoperability Resources ([[FHIR]]), [http://json.org JSON], or other encoding system. In these models the actual health care data are not encoded in the blockchain, but are merely references pointing to where the data reside, such as at institutions or in a "data lake" <ref>Linn LA, Koo MB. Blockchain For Health Data and Its Potential Use in Health IT and Health Care Related Research. 2014;1–10.</ref>. Similarly, a group out of China described an app called Healthcare Data Gateway (HGD) that allows patients to view and directly control rule-based access to their health records with a smart phone interface and authentication provided by a blockchain network <ref>Yue X, Wang H, Jin D, Li M, Jiang W. Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst [Internet]. 2016 Oct;40(10):218. Available from: http://dx.doi.org/10.1007/s10916-016-0574-6</ref>. These ideas support the concept of patient-owned medical data, and would have the effect of decentralization of medical records in ways that are as yet undetermined.<br />
<br />
=== Health Research Integrity ===<br />
Academic research is a major driver of advances in health care, but in the setting of limited funding and publication pressures on researchers significant concerns have been raised regarding research integrity<ref>Titus SL, Wells J a, Rhoades LJ. Repairing research integrity. Nature [Internet]. 2008 Jun 19;453(7198):980–2. Available from: http://www.ncbi.nlm.nih.gov/pubmed/18563131</ref>. Organizations such as [http://clinicaltrials.gov ClinicalTrials.gov] and others have been developed to help drive researchers to define endpoints and analysis prior to conducting clinical trials and other studies. As it represents an immutable, verifiable record of events and transactions, the blockchain has been proposed as a potential decentralized resources for helping to ensure biomedical research integrity. Benjamin Carlisle<ref>Carlisle BG. Proof of prespecified endpoints in medical research with the bitcoin blockchain [Internet]. 2014. Available from: http://www.bgcarlisle.com/blog/2014/08/25/proof-of-prespecified-endpoints-in-medical-research-with-the-bitcoin-blockchain/</ref>, followed by several researchers from the UK<ref>Irving G, Holden J. How blockchain-timestamped protocols could improve the trustworthiness of medical science. F1000Research [Internet]. 2016;5:222. Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4866630/</ref>, proposed in 2014 that researchers could use the blockchain to record pre-specified aspects of their projects, including the study design, analysis plan, and data structure, among others, which could later be verified by consumers of the literature to decrease bias that may be introduced in post-hoc analysis<ref>Slade E, Drysdale H, Goldacre B, COMPare Team. Discrepancies Between Prespecified and Reported Outcomes. Ann Intern Med [Internet]. 2016 Mar 1;164(5):374. Available from: http://www.ncbi.nlm.nih.gov/pubmed/26720309</ref>. The blockchain also offers the potential ability to verify the integrity of actual research data and analysis by outside observers, even if the data themselves are not made publicly available. These types of implementations may lead to improvements in both the integrity of biomedical research as well as bolster public trust in medical research.<br />
<br />
=== Personal Health Records ===<br />
This concept dovetails with the idea of HIE using the blockchain, but focuses more on the secure maintenance of a personal health record (PHR) by patients. No production PHR has been released based on this technology, but concepts such as MedVault <ref>Baxendale G. Can Blockchain Revolutionise EPRs? [Internet]. Vol. 58, ITNOW. 2016. p. 38–9. Available from: http://itnow.oxfordjournals.org/lookup/doi/10.1093/itnow/bww017</ref> use alternative blockchains such as [http://www.Colu.com Colu] to store patient data directly on the blockchain. Others such as [https://devpost.com/software/ehealthwallet eHealthWallet] have also developed prototype PHRs based on the blockchain. Patients could then share or authorize doctors and other health entities to access and modify their data.<br />
<br />
The majority of the proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference<ref>Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230</ref><ref>Yue, X., Wang, H., Jin, D., Li, M., & Jiang, W. (2016). Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst, 40(10), 218. doi:10.1007/s10916-016-0574-6</ref>. <br />
* In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care.<br />
* As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed.<br />
* A blockchain-enabled smart contracts controlled by the patient can be used to authorize direct sharing of medical record between institutions. Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability<ref>Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230</ref>: <br />
* Digital access rules: The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application<br />
* Data aggregation: Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health<br />
* Data liquidity: Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc.<br />
* Patient identity: Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems<br />
* Data immutability: Since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time.<br />
<br />
=== Storage of Health Care Data ===<br />
Most of the previous examples use the blockchain not as a direct data storage medium, but instead as a secure reference point for identities, access, and data locations. At least one group from a company called Tierion, which partners with the [http://www.2.forms.healthcare.philips.com/blockchainlabs Philips Blockchain Lab ], has produced a concept called Chainpoint<ref>Vaughan AW, Bukowski J, Wilkinson S, Sporny CM, Shea R, Allen C, et al. Chainpoint: A scalable protocol for anchoring data in the blockchain and generating blockchain receipts [Internet]. 2016. Available from: https://tierion.com/chainpoint</ref>, which proposes to use a [https://proofofexistence.com/about Proof of Existence] concept and Merkle Roots<ref>Merkle RC. PROTOCOLS FOR PUBUC KEY CRYPTOSYSTEMS. In: IEEE Symposium on Security and Privacy [Internet]. 1980. p. 122–34. Available from: http://www.merkle.com/papers/Protocols.pdf</ref> to efficiently store actual patient records on the blockchain without imposing excessive transaction demands on the system.<br />
<br />
=== Billing and Claims Adjudication ===<br />
Blockchain system can help reduce administrative costs and time while automating claims adjudication and payment processing using smart contracts. For example - a smart contract is set up between payer or insurance company, provider, and patient such that when the patient sees a provider, or if a procedure is done, an entry is recorded in the blockchain. Based on the criteria set, the contract can automatically issue reimbursement from the payer as well as co-pay from the patient without having to wait for the insurance approval.<ref>Srinivasan, P. (2017, November 9). Healthcare Blockchain: How Smart Contracts Could Revolutionize Care Delivery. Prolifics. Retrieved from: https://www.prolifics.com/blog/healthcare-blockchain-how-smart-contracts-could-revolutionize-care-delivery</ref><br />
<br />
=== Drug Supply Chain and Prescription Management ===<br />
Counterfeit drugs are a major problem especially in the developing country where it is estimated that about 1 in 10 medical products are counterfeit <ref>WHO. (2017, November 28). 1 in 10 medical products in developing countries is substandard or falsified. Retrieved from: http://www.who.int/en/news-room/detail/28-11-2017-1-in-10-medical-products-in-developing-countries-is-substandard-or-falsified</ref>. Ensuring the integrity of the drug and maintaining a robust audit trail is a must to ensure patient safety. Similarly, this platform can be used in prescription drug management and track history and authenticate prescriptions using smart-contracts. <br />
<br />
=== Few Examples of Current Use Cases and Future Development ===<br />
<br />
* MedRec- it is based on Ethereum platform and focuses on medical data management using smart contracts like managing permissions and authentication processes, data sharing in an interoperable environment between healthcare systems and maintaining an audit log. <ref>Azaria, A., Ekblaw, A., Vieira, T., & Lippman, A. (2016, August 22-24). MedRec: Using Blockchain for Medical Data Access and Permission Management. 2016 2nd International Conference on Open and Big Data (OBD). doi:10.1109/obd.2016.11</ref><br />
<br />
* Guardtime- also focuses on medical data management and has partnered with e-Health authority of Estonia to secure the country's database of health records <ref>Ruubel M. (2016, February 12). Estonian eHealth Authority Partners with Guardtime to Accelerate Transparency and Auditability in Health Care. Retrieved from: https://guardtime.com/blog/estonian-ehealth-partners-guardtime-blockchain-based-transparency</ref>. Also, recently, MyPCR smartphone platform from Guardtime has partnered with Instant Access Medical and Healthcare Gateway in the UK for patient health data management and verification of medication adherence. <ref>Ruubel M. (2018, June 20). World’s first blockchain-supported Personal Care Record Platform launched by Guardtime and partners to up to 30 million NHS patients in the UK. Retrieved from: https://guardtime.com/blog/world-s-first-blockchain-supported-personal-care-record-platform-launched-by-guardtime-and-partners</ref> <br />
<br />
* Blockchain Health- created for healthcare research data management where users can individually authorize the release of their health information to researchers as well as track the use of their data. <ref>BlockchainHealth. (2016). Blockchain for health research. Retrieved from: https://blockchainhealth.co/</ref><br />
<br />
* BlockMedx- it is a startup company which intends to use the blockchain platform to transmit DEA controlled drug prescriptions from physicians to pharmacies and then to patients securely. <ref>BlockMedx. (2018). Retrieved from: https://blockmedx.com/en/</ref><br />
<br />
* MediLedger- another pharmaceutical supply chain management startup company who has partnered with several drug manufacturers and aims to provide an open, secure and interoperable network. <ref>MediLedger. (2018). The MediLedger Project. Retrieved from: https://mediledger.com/</ref><br />
<br />
* Drug and Pharmacy Verification - [https://devpost.com/software/veripharm VeriPharm] has developed a proof of concept that would help track and verify pharmaceuticals from the raw materials to the final product administered to patients.<br />
<br />
* Appointment Scheduling on the Blockchain - [https://devpost.com/software/dhva-appointment-blocks dhva-apointment-blocks]<br />
<br />
* Care Coordination - Projects such as [https://devpost.com/software/simplyvitahlth simplyvitahlth] are geared toward coordinating care between multiple providers and at different institutions to ensure that complex care pathways are being followed appropriately.<br />
<br />
<br />
There are many more potential use-cases for blockchain technology within healthcare, and undoubtedly we will continue to see development in this area in coming years. In 2016, a consortium of sponsors led by [https://gem.co/ Gem] (Whitepaper)<ref>Wood C, Winton B, Carter K, Benkert S, Dodd L, Bradley J, et al. How Blockchain Technology Can Enhance Ehr Operability [Internet]. 2016. Available from: http://research.ark-invest.com/blockchain-and-healthcare</ref> held the first healthcare oriented blockchain conference, [https://godistributed.com/health Distributed: Health] in Nashville, TN. Similarly, the Office of the National Coordinator (ONC) Tech Lab had issued a Blockchain Challenge in July, 2016.<ref>https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab</ref><br />
* The list of submissions and awards can be found [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab here]<br />
<br />
As the healthcare blockchain community grows, gatherings such as these will likely increase and blockchain technologies will increasingly be introduced at major medical conferences.<br />
<br />
== References ==<br />
<references /><br />
<br />
Submitted by Sandeep Regmi<br />
[[Category: BMI512-FALL-18]]<br />
<br />
Submitted by Ben Orwoll<br />
<br />
[[Category: BMI512-FALL-16]]<br />
[[Category: Reviews]]<br />
[[Category: Other Technologies]]</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/The_Blockchain_in_HealthcareThe Blockchain in Healthcare2018-10-19T03:08:54Z<p>Phamnh: /* Possible Solutions: */</p>
<hr />
<div>The blockchain is an idea centered around the concept of a secure, digital ledger system that provides a system for efficient, auditable transactions of almost any type between entities <ref>Tapscott D, Tapscott A. Blockchain Revolution: How the Technology Behind Bitcoin Is Changing Money, Business, and the World. United States: Portfolio; 2016. 1-368 p.</ref>. All information related to blockchain transactions is at once both independently verifiable by all (even outside) parties as correct and also inscrutable to entities without explicit permission. The first and probably most well-known implementation of blockchain technology is [https://bitcoin.org Bitcoin] <ref name="BTC">Nakamoto S. Bitcoin: A Peer-to-Peer Electronic Cash System. WwwBitcoinOrg [Internet]. 2008;9. Available from: https://bitcoin.org/bitcoin.pdf</ref>, but there has been a massive expansion of blockchain use-cases since Bitcoin's initial introduction.<br />
<br />
<br />
<br />
== What is the Blockchain? ==<br />
<br />
First, it should be clear that there is no one blockchain to rule them all. "The Blockchain," as it is often referred, really is a concept of a series (chain) of interrelated sets (blocks) of encrypted information. Hence a chain of blocks, or blockchain. There are many such blockchains in existence, and one could choose to do transactions on any one of them or create a new blockchain.<br />
<br />
<br />
An important aspect of most blockchains is that they are designed to be maintained on a distributed network of multiple nodes. Each node holds a complete copy of the blockchain and adds each sequential new block as it is created. This system allows every transaction on the blockchain to be verified by any or all of the nodes in the network, and also makes it very difficult for the information held in the blockchain to become lost or unavailable if any one or even most of the nodes go offline.<br />
<br />
<br />
Transactions that are set to be added to the blockchain are added to the newest block as soon as it is created. This makes the continued existence of the blockchain dependent on the creation of new blocks. There are several main methods for the creation of new blocks on the network, and the choice of method depends somewhat on the purpose of the blockchain in question. Bitcoin, the first cryptocurrency, uses a method called [https://en.wikipedia.org/wiki/Proof-of-work_system Proof of Work System (Wikipedia)]:<br />
* In the traditional Proof of Work System, each block validator, or "miner," competes to validate the block by processing a task. The winner is the first person to complete this task. The chance of completion of the task is random based on a hash function, but increases with the more "work" a person puts into the task. The system can automatically vary the difficulty of the task to limit the speed of block generation. The winner is credited for his/her work by a small amount of currency. <br />
<br />
<br />
The blockchain has moved beyond simply processing transactions of cryptocurrency such as Bitcoin. Any data that can be encoded into a cryptographic [https://en.wikipedia.org/wiki/Hash_function hash] can be added to a blockchain. Various different ideas have been proposed, and I will not attempt to list them here, but they are wide ranging. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0<ref>Swan, M. (2015). Blockchain: Blueprint for a new economy: " O'Reilly Media, Inc."</ref>. Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education.<br />
<br />
<br />
=== Blockchain Development Groups ===<br />
Certainly a non-exhaustive list . . .<br />
<br />
* [https://bitcoin.org/en/ Bitcoin]<br />
<br />
* [https://hyperledger.org The Hyperledger Project]<br />
<br />
* [https://ethereum.org The Ethereum Project]<br />
<br />
* [https://r3cev.com/blog/2016/4/4/introducing-r3-corda-a-distributed-ledger-designed-for-financial-services The CORDA Platform]<br />
<br />
* [http://www.muskokagroup.org/ The Muskoka Group]<br />
<br />
* [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab The ONC Tech Lab]<br />
<br />
== Blockchain Use Cases ==<br />
<br />
=== Cryptocurrency ===<br />
Bitcoin (BTC) was the first cryptocurrency based on the blockchain and was developed by someone calling himself (or herself) Satoshi Nakamoto. The protocol was introduced in 2008 after the publication of a white paper<ref name="BTC" /> describing the algorithm and the mechanisms for generation and distribution of BTC. At this point there are hundreds of cryptocurrencies in circulation according to [http://wikipedia.org Wikipedia], many of which are based on the Bitcoin blockchain, but only a few have gone into widespread use<ref>https://en.wikipedia.org/wiki/List_of_cryptocurrencies</ref>.<br />
<br />
=== Smart Contracts ===<br />
One of the major potential functions of blockchain technology is through the creation of smart contracts. Various components of contracts, including proof of the involved parties, requirements for completion, and actions upon completion of the contract can be encoded in blocks. These can then be added to a blockchain and become available for independent verification, which can even lead to automatic processing of contracts when their requirements have been fulfilled.<br />
<br />
Smart contracts are scripts which have various rules and logic that automatically execute when those rules are met. Smart contracts allow heavily automated workflows between transacting parties in the network while maintaining anonymity. Once the contract has been executed, one can take custody over assets or pre-defined payments can be issued. <ref>Christidis, K & Devetsikiotis, M. (2016, May 10). Blockchains and Smart Contracts for the Internet of Things. IEEE Access, 4, 2292-2303. doi: 10.1109/ACCESS.2016.2566339</ref> They are importantly different in the sense that they are stored on a distributed network and they can be verified as true without knowledge of the contract specifications <ref>https://bitsonblocks.net/2016/02/01/a-gentle-introduction-to-smart-contracts/</ref>.<br />
<br />
[https://ethereum.org The Ethereum Project] was one of the first to introduce the concept of smart contracts using their alternative blockchain and currency token, [https://www.ethereum.org/ether ether].<br />
<br />
=== Securities Exchanges and Finance ===<br />
<br />
One of the hottest arenas for blockchain development currently is in the financial markets, an extension of the original cryptocurrency use cases for the blockchain. Multiple stock markets and other financial firms have initiated investigations and pilot projects into the feasibility and utility of the blockchain for contracts and tracking of financial instruments. NASDAQ has been one of the first major markets to put blockchain technology into use, and has released some information on its implementation, called Linq <ref>http://ir.nasdaq.com/releasedetail.cfm?releaseid=948326</ref><ref>http://www.coindesk.com/hands-on-with-linq-nasdaqs-private-markets-blockchain-project/</ref>. The cryptocurrency website [http://www.coindesk.com Coindesk] has also produced a list of 10 exchanges using or investigating blockchain technologies<ref>http://www.coindesk.com/10-stock-exchanges-blockchain/</ref>.<br />
<br />
<br />
Additionally, financial firms such as Visa have been experimenting with the blockchain for keeping track of transactions as well as with proof of concept applications such as remittance<ref>http://www.coindesk.com/hands-on-with-visa-europes-bitcoin-remittance-app/</ref>.<br />
<br />
== Advantages and Disadvantages of Blockchain ==<br />
<br />
Blockchain is a novel concept and is being explored in various sectors. While there may be several applications and limitations of this technology in future, some of them are highlighted below<ref>Fauvel, W. (2017, August 11). Blockchain Advantage and Disadvantages. Medium. Retrieved from: https://medium.com/nudjed/blockchain-advantage-and-disadvantages-e76dfde3bbc0</ref>:<br />
<br />
=== Pros: ===<br />
# Distributed: There is no single owner of the database. As anyone can contribute and be a part of the network, the risks of data tampering and fraud are minimal. As Nakamoto <ref name="BTC" /> mentioned, as long as the majority of nodes are honest, a random attacker would not be able to alter the history.<br />
# Trustless: As every node in the network will have a copy of the blockchain and they verify the transactions independently. Hence, this system allows transaction even if the parties don't trust each other.<br />
# Immutable: Once the transaction is verified and embedded in the blockchain, it is almost impossible to undo it, and the complexity increases with time as more blocks are added downstream. This allows keeping a track of accurate events that occurred through the history.<br />
# Decentralized: There is no middleman like banks or data owners. This helps avoid manipulation of the market by the owners.<br />
<br />
<br />
=== Cons: ===<br />
# Waste of resources: As several nodes are running and utilizing a huge amount of computing power and electricity to verify and maintain the blockchain, there is more than required redundancy. <br />
# Higher cost for less value: With time, the use of network increases and the complexity of the hashing algorithm also increases. Hence, more resources are required for the same amount of work. This increases the cost of work and transactions gets slower, as miners prioritize the transactions with higher incentives causing a backlog the transactions with smaller values. <br />
# Difficulty to keep up with the size of the block: As the size continues to grow along with the complexity to solve the calculation, new nodes with smaller computing power will have difficulty joining the network and likewise, the older and slower nodes will gradually fade with decreasing incentive for the work. Hence, like Darwin’s theory of the "survival of the fittest", a few larger nodes will dominate the network creating more and more centralization of the system. <br />
# Speculative market: Due to the lack of proper regulation of this system, the market is subject to a great volatility and thus making it risky for investors. <br />
# Immutable smart contracts: As there are clear advantages of having permanent and immutable records, at the same time, there is a bitter flipside to this. For example, if there is a flaw with code that can compromise the system, it is also irreparable and creates the opportunity for the attackers to exploit the same flaw repetitively in future. As time progresses, the capability of repairing the error will be even more complex.<br />
<br />
<br />
<br />
=== Possible Solutions: ===<br />
* The issues with resource wastefulness and diminishing return of investment are mainly an issue with Proof-of-Work Systems, and can be improved with new blockchain innovations such as [https://en.bitcoin.it/wiki/Proof_of_Stake Proof of Stake (Bitcoin Wiki)] or blockchain scaling<ref>Croman, Kyle, et al. "On scaling decentralized blockchains." International Conference on Financial Cryptography and Data Security. Springer, Berlin, Heidelberg, 2016.</ref><br />
** There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake<ref>Siim, Janno. "Proof-of-Stake."</ref>. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker.<br />
** Currently, all computers that participate in mining a blockchain process every transaction. This is very slow and resource wasteful. A solution to this is to calculate how many computers will be needed to validate a new block, and give the task of verifying a transaction to those computers. This will allow parallel processing and speed up transactions. At this point, the details behind how to manage this division of tasks without compromising security still being worked out.<br />
<br />
== Potential Use Cases in Healthcare ==<br />
Though there has yet to be a breakthrough report or use-case for blockchain technology in healthcare, there are many potential ways that the blockchain could be implemented within the current healthcare structure. Any list will likely be incomplete, but these examples represent some of the published and available literature on blockchain implementations in health.<br />
<br />
=== Health Information Exchange (HIE) ===<br />
One major area that blockchains may be able to facilitate is the secure access to and communication of patient health records between individuals and institutions. There have been multiple white papers published on the topic, including groups from the Mayo Clinic <ref>Peterson K, Deeduvanu R, Kanjamala P, Boles K. A Blockchain-Based Approach to Health Information Exchange Networks. (1):1–10.</ref> and MIT <ref>Ekblaw A, Azaria A, Halamka JD, Lippman A, Original I, Vieira T. A Case Study for Blockchain in Healthcare: “ MedRec ” prototype for electronic health records and medical research data MedRec: Using Blockchain for Medical Data Access and Permission Management [Internet]. 2016. Available from: https://www.healthit.gov/sites/default/files/5-56-onc_blockchainchallenge_mitwhitepaper.pdf</ref> who described a system for patient information exchange based on blockchain technology that would allow patient-controlled access to records across institutions using HL7 Fast Healthcare Interoperability Resources ([[FHIR]]), [http://json.org JSON], or other encoding system. In these models the actual health care data are not encoded in the blockchain, but are merely references pointing to where the data reside, such as at institutions or in a "data lake" <ref>Linn LA, Koo MB. Blockchain For Health Data and Its Potential Use in Health IT and Health Care Related Research. 2014;1–10.</ref>. Similarly, a group out of China described an app called Healthcare Data Gateway (HGD) that allows patients to view and directly control rule-based access to their health records with a smart phone interface and authentication provided by a blockchain network <ref>Yue X, Wang H, Jin D, Li M, Jiang W. Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst [Internet]. 2016 Oct;40(10):218. Available from: http://dx.doi.org/10.1007/s10916-016-0574-6</ref>. These ideas support the concept of patient-owned medical data, and would have the effect of decentralization of medical records in ways that are as yet undetermined.<br />
<br />
=== Health Research Integrity ===<br />
Academic research is a major driver of advances in health care, but in the setting of limited funding and publication pressures on researchers significant concerns have been raised regarding research integrity<ref>Titus SL, Wells J a, Rhoades LJ. Repairing research integrity. Nature [Internet]. 2008 Jun 19;453(7198):980–2. Available from: http://www.ncbi.nlm.nih.gov/pubmed/18563131</ref>. Organizations such as [http://clinicaltrials.gov ClinicalTrials.gov] and others have been developed to help drive researchers to define endpoints and analysis prior to conducting clinical trials and other studies. As it represents an immutable, verifiable record of events and transactions, the blockchain has been proposed as a potential decentralized resources for helping to ensure biomedical research integrity. Benjamin Carlisle<ref>Carlisle BG. Proof of prespecified endpoints in medical research with the bitcoin blockchain [Internet]. 2014. Available from: http://www.bgcarlisle.com/blog/2014/08/25/proof-of-prespecified-endpoints-in-medical-research-with-the-bitcoin-blockchain/</ref>, followed by several researchers from the UK<ref>Irving G, Holden J. How blockchain-timestamped protocols could improve the trustworthiness of medical science. F1000Research [Internet]. 2016;5:222. Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4866630/</ref>, proposed in 2014 that researchers could use the blockchain to record pre-specified aspects of their projects, including the study design, analysis plan, and data structure, among others, which could later be verified by consumers of the literature to decrease bias that may be introduced in post-hoc analysis<ref>Slade E, Drysdale H, Goldacre B, COMPare Team. Discrepancies Between Prespecified and Reported Outcomes. Ann Intern Med [Internet]. 2016 Mar 1;164(5):374. Available from: http://www.ncbi.nlm.nih.gov/pubmed/26720309</ref>. The blockchain also offers the potential ability to verify the integrity of actual research data and analysis by outside observers, even if the data themselves are not made publicly available. These types of implementations may lead to improvements in both the integrity of biomedical research as well as bolster public trust in medical research.<br />
<br />
=== Personal Health Records ===<br />
This concept dovetails with the idea of HIE using the blockchain, but focuses more on the secure maintenance of a personal health record (PHR) by patients. No production PHR has been released based on this technology, but concepts such as MedVault <ref>Baxendale G. Can Blockchain Revolutionise EPRs? [Internet]. Vol. 58, ITNOW. 2016. p. 38–9. Available from: http://itnow.oxfordjournals.org/lookup/doi/10.1093/itnow/bww017</ref> use alternative blockchains such as [http://www.Colu.com Colu] to store patient data directly on the blockchain. Others such as [https://devpost.com/software/ehealthwallet eHealthWallet] have also developed prototype PHRs based on the blockchain. Patients could then share or authorize doctors and other health entities to access and modify their data.<br />
<br />
The majority of the proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference<ref>Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230</ref><ref>Yue, X., Wang, H., Jin, D., Li, M., & Jiang, W. (2016). Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst, 40(10), 218. doi:10.1007/s10916-016-0574-6</ref>. <br />
* In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care.<br />
* As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed.<br />
* A blockchain-enabled smart contracts controlled by the patient can be used to authorize direct sharing of medical record between institutions. Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability<ref>Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230</ref>: <br />
* Digital access rules: The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application<br />
* Data aggregation: Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health<br />
* Data liquidity: Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc.<br />
* Patient identity: Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems<br />
* Data immutability: Since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time.<br />
<br />
=== Storage of Health Care Data ===<br />
Most of the previous examples use the blockchain not as a direct data storage medium, but instead as a secure reference point for identities, access, and data locations. At least one group from a company called Tierion, which partners with the [http://www.2.forms.healthcare.philips.com/blockchainlabs Philips Blockchain Lab ], has produced a concept called Chainpoint<ref>Vaughan AW, Bukowski J, Wilkinson S, Sporny CM, Shea R, Allen C, et al. Chainpoint: A scalable protocol for anchoring data in the blockchain and generating blockchain receipts [Internet]. 2016. Available from: https://tierion.com/chainpoint</ref>, which proposes to use a [https://proofofexistence.com/about Proof of Existence] concept and Merkle Roots<ref>Merkle RC. PROTOCOLS FOR PUBUC KEY CRYPTOSYSTEMS. In: IEEE Symposium on Security and Privacy [Internet]. 1980. p. 122–34. Available from: http://www.merkle.com/papers/Protocols.pdf</ref> to efficiently store actual patient records on the blockchain without imposing excessive transaction demands on the system.<br />
<br />
=== Billing and Claims Adjudication ===<br />
Blockchain system can help reduce administrative costs and time while automating claims adjudication and payment processing using smart contracts. For example - a smart contract is set up between payer or insurance company, provider, and patient such that when the patient sees a provider, or if a procedure is done, an entry is recorded in the blockchain. Based on the criteria set, the contract can automatically issue reimbursement from the payer as well as co-pay from the patient without having to wait for the insurance approval.<ref>Srinivasan, P. (2017, November 9). Healthcare Blockchain: How Smart Contracts Could Revolutionize Care Delivery. Prolifics. Retrieved from: https://www.prolifics.com/blog/healthcare-blockchain-how-smart-contracts-could-revolutionize-care-delivery</ref><br />
<br />
=== Drug Supply Chain and Prescription Management ===<br />
Counterfeit drugs are a major problem especially in the developing country where it is estimated that about 1 in 10 medical products are counterfeit <ref>WHO. (2017, November 28). 1 in 10 medical products in developing countries is substandard or falsified. Retrieved from: http://www.who.int/en/news-room/detail/28-11-2017-1-in-10-medical-products-in-developing-countries-is-substandard-or-falsified</ref>. Ensuring the integrity of the drug and maintaining a robust audit trail is a must to ensure patient safety. Similarly, this platform can be used in prescription drug management and track history and authenticate prescriptions using smart-contracts. <br />
<br />
=== Few Examples of Current Use Cases and Future Development ===<br />
<br />
* MedRec- it is based on Ethereum platform and focuses on medical data management using smart contracts like managing permissions and authentication processes, data sharing in an interoperable environment between healthcare systems and maintaining an audit log. <ref>Azaria, A., Ekblaw, A., Vieira, T., & Lippman, A. (2016, August 22-24). MedRec: Using Blockchain for Medical Data Access and Permission Management. 2016 2nd International Conference on Open and Big Data (OBD). doi:10.1109/obd.2016.11</ref><br />
<br />
* Guardtime- also focuses on medical data management and has partnered with e-Health authority of Estonia to secure the country's database of health records <ref>Ruubel M. (2016, February 12). Estonian eHealth Authority Partners with Guardtime to Accelerate Transparency and Auditability in Health Care. Retrieved from: https://guardtime.com/blog/estonian-ehealth-partners-guardtime-blockchain-based-transparency</ref>. Also, recently, MyPCR smartphone platform from Guardtime has partnered with Instant Access Medical and Healthcare Gateway in the UK for patient health data management and verification of medication adherence. <ref>Ruubel M. (2018, June 20). World’s first blockchain-supported Personal Care Record Platform launched by Guardtime and partners to up to 30 million NHS patients in the UK. Retrieved from: https://guardtime.com/blog/world-s-first-blockchain-supported-personal-care-record-platform-launched-by-guardtime-and-partners</ref> <br />
<br />
* Blockchain Health- created for healthcare research data management where users can individually authorize the release of their health information to researchers as well as track the use of their data. <ref>BlockchainHealth. (2016). Blockchain for health research. Retrieved from: https://blockchainhealth.co/</ref><br />
<br />
* BlockMedx- it is a startup company which intends to use the blockchain platform to transmit DEA controlled drug prescriptions from physicians to pharmacies and then to patients securely. <ref>BlockMedx. (2018). Retrieved from: https://blockmedx.com/en/</ref><br />
<br />
* MediLedger- another pharmaceutical supply chain management startup company who has partnered with several drug manufacturers and aims to provide an open, secure and interoperable network. <ref>MediLedger. (2018). The MediLedger Project. Retrieved from: https://mediledger.com/</ref><br />
<br />
* Drug and Pharmacy Verification - [https://devpost.com/software/veripharm VeriPharm] has developed a proof of concept that would help track and verify pharmaceuticals from the raw materials to the final product administered to patients.<br />
<br />
* Appointment Scheduling on the Blockchain - [https://devpost.com/software/dhva-appointment-blocks dhva-apointment-blocks]<br />
<br />
* Care Coordination - Projects such as [https://devpost.com/software/simplyvitahlth simplyvitahlth] are geared toward coordinating care between multiple providers and at different institutions to ensure that complex care pathways are being followed appropriately.<br />
<br />
<br />
There are many more potential use-cases for blockchain technology within healthcare, and undoubtedly we will continue to see development in this area in coming years. In 2016, a consortium of sponsors led by [https://gem.co/ Gem] (Whitepaper)<ref>Wood C, Winton B, Carter K, Benkert S, Dodd L, Bradley J, et al. How Blockchain Technology Can Enhance Ehr Operability [Internet]. 2016. Available from: http://research.ark-invest.com/blockchain-and-healthcare</ref> held the first healthcare oriented blockchain conference, [https://godistributed.com/health Distributed: Health] in Nashville, TN. Similarly, the Office of the National Coordinator (ONC) Tech Lab had issued a Blockchain Challenge in July, 2016.<ref>https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab</ref><br />
* The list of submissions and awards can be found [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab here]<br />
<br />
As the healthcare blockchain community grows, gatherings such as these will likely increase and blockchain technologies will increasingly be introduced at major medical conferences.<br />
<br />
== References ==<br />
<references /><br />
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Submitted by Sandeep Regmi<br />
[[Category: BMI512-FALL-18]]<br />
<br />
Submitted by Ben Orwoll<br />
<br />
[[Category: BMI512-FALL-16]]<br />
[[Category: Reviews]]<br />
[[Category: Other Technologies]]</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/The_Blockchain_in_HealthcareThe Blockchain in Healthcare2018-10-19T03:08:39Z<p>Phamnh: /* Advantages and Disadvantages of Blockchain */</p>
<hr />
<div>The blockchain is an idea centered around the concept of a secure, digital ledger system that provides a system for efficient, auditable transactions of almost any type between entities <ref>Tapscott D, Tapscott A. Blockchain Revolution: How the Technology Behind Bitcoin Is Changing Money, Business, and the World. United States: Portfolio; 2016. 1-368 p.</ref>. All information related to blockchain transactions is at once both independently verifiable by all (even outside) parties as correct and also inscrutable to entities without explicit permission. The first and probably most well-known implementation of blockchain technology is [https://bitcoin.org Bitcoin] <ref name="BTC">Nakamoto S. Bitcoin: A Peer-to-Peer Electronic Cash System. WwwBitcoinOrg [Internet]. 2008;9. Available from: https://bitcoin.org/bitcoin.pdf</ref>, but there has been a massive expansion of blockchain use-cases since Bitcoin's initial introduction.<br />
<br />
<br />
<br />
== What is the Blockchain? ==<br />
<br />
First, it should be clear that there is no one blockchain to rule them all. "The Blockchain," as it is often referred, really is a concept of a series (chain) of interrelated sets (blocks) of encrypted information. Hence a chain of blocks, or blockchain. There are many such blockchains in existence, and one could choose to do transactions on any one of them or create a new blockchain.<br />
<br />
<br />
An important aspect of most blockchains is that they are designed to be maintained on a distributed network of multiple nodes. Each node holds a complete copy of the blockchain and adds each sequential new block as it is created. This system allows every transaction on the blockchain to be verified by any or all of the nodes in the network, and also makes it very difficult for the information held in the blockchain to become lost or unavailable if any one or even most of the nodes go offline.<br />
<br />
<br />
Transactions that are set to be added to the blockchain are added to the newest block as soon as it is created. This makes the continued existence of the blockchain dependent on the creation of new blocks. There are several main methods for the creation of new blocks on the network, and the choice of method depends somewhat on the purpose of the blockchain in question. Bitcoin, the first cryptocurrency, uses a method called [https://en.wikipedia.org/wiki/Proof-of-work_system Proof of Work System (Wikipedia)]:<br />
* In the traditional Proof of Work System, each block validator, or "miner," competes to validate the block by processing a task. The winner is the first person to complete this task. The chance of completion of the task is random based on a hash function, but increases with the more "work" a person puts into the task. The system can automatically vary the difficulty of the task to limit the speed of block generation. The winner is credited for his/her work by a small amount of currency. <br />
<br />
<br />
The blockchain has moved beyond simply processing transactions of cryptocurrency such as Bitcoin. Any data that can be encoded into a cryptographic [https://en.wikipedia.org/wiki/Hash_function hash] can be added to a blockchain. Various different ideas have been proposed, and I will not attempt to list them here, but they are wide ranging. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0<ref>Swan, M. (2015). Blockchain: Blueprint for a new economy: " O'Reilly Media, Inc."</ref>. Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education.<br />
<br />
<br />
=== Blockchain Development Groups ===<br />
Certainly a non-exhaustive list . . .<br />
<br />
* [https://bitcoin.org/en/ Bitcoin]<br />
<br />
* [https://hyperledger.org The Hyperledger Project]<br />
<br />
* [https://ethereum.org The Ethereum Project]<br />
<br />
* [https://r3cev.com/blog/2016/4/4/introducing-r3-corda-a-distributed-ledger-designed-for-financial-services The CORDA Platform]<br />
<br />
* [http://www.muskokagroup.org/ The Muskoka Group]<br />
<br />
* [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab The ONC Tech Lab]<br />
<br />
== Blockchain Use Cases ==<br />
<br />
=== Cryptocurrency ===<br />
Bitcoin (BTC) was the first cryptocurrency based on the blockchain and was developed by someone calling himself (or herself) Satoshi Nakamoto. The protocol was introduced in 2008 after the publication of a white paper<ref name="BTC" /> describing the algorithm and the mechanisms for generation and distribution of BTC. At this point there are hundreds of cryptocurrencies in circulation according to [http://wikipedia.org Wikipedia], many of which are based on the Bitcoin blockchain, but only a few have gone into widespread use<ref>https://en.wikipedia.org/wiki/List_of_cryptocurrencies</ref>.<br />
<br />
=== Smart Contracts ===<br />
One of the major potential functions of blockchain technology is through the creation of smart contracts. Various components of contracts, including proof of the involved parties, requirements for completion, and actions upon completion of the contract can be encoded in blocks. These can then be added to a blockchain and become available for independent verification, which can even lead to automatic processing of contracts when their requirements have been fulfilled.<br />
<br />
Smart contracts are scripts which have various rules and logic that automatically execute when those rules are met. Smart contracts allow heavily automated workflows between transacting parties in the network while maintaining anonymity. Once the contract has been executed, one can take custody over assets or pre-defined payments can be issued. <ref>Christidis, K & Devetsikiotis, M. (2016, May 10). Blockchains and Smart Contracts for the Internet of Things. IEEE Access, 4, 2292-2303. doi: 10.1109/ACCESS.2016.2566339</ref> They are importantly different in the sense that they are stored on a distributed network and they can be verified as true without knowledge of the contract specifications <ref>https://bitsonblocks.net/2016/02/01/a-gentle-introduction-to-smart-contracts/</ref>.<br />
<br />
[https://ethereum.org The Ethereum Project] was one of the first to introduce the concept of smart contracts using their alternative blockchain and currency token, [https://www.ethereum.org/ether ether].<br />
<br />
=== Securities Exchanges and Finance ===<br />
<br />
One of the hottest arenas for blockchain development currently is in the financial markets, an extension of the original cryptocurrency use cases for the blockchain. Multiple stock markets and other financial firms have initiated investigations and pilot projects into the feasibility and utility of the blockchain for contracts and tracking of financial instruments. NASDAQ has been one of the first major markets to put blockchain technology into use, and has released some information on its implementation, called Linq <ref>http://ir.nasdaq.com/releasedetail.cfm?releaseid=948326</ref><ref>http://www.coindesk.com/hands-on-with-linq-nasdaqs-private-markets-blockchain-project/</ref>. The cryptocurrency website [http://www.coindesk.com Coindesk] has also produced a list of 10 exchanges using or investigating blockchain technologies<ref>http://www.coindesk.com/10-stock-exchanges-blockchain/</ref>.<br />
<br />
<br />
Additionally, financial firms such as Visa have been experimenting with the blockchain for keeping track of transactions as well as with proof of concept applications such as remittance<ref>http://www.coindesk.com/hands-on-with-visa-europes-bitcoin-remittance-app/</ref>.<br />
<br />
== Advantages and Disadvantages of Blockchain ==<br />
<br />
Blockchain is a novel concept and is being explored in various sectors. While there may be several applications and limitations of this technology in future, some of them are highlighted below<ref>Fauvel, W. (2017, August 11). Blockchain Advantage and Disadvantages. Medium. Retrieved from: https://medium.com/nudjed/blockchain-advantage-and-disadvantages-e76dfde3bbc0</ref>:<br />
<br />
=== Pros: ===<br />
# Distributed: There is no single owner of the database. As anyone can contribute and be a part of the network, the risks of data tampering and fraud are minimal. As Nakamoto <ref name="BTC" /> mentioned, as long as the majority of nodes are honest, a random attacker would not be able to alter the history.<br />
# Trustless: As every node in the network will have a copy of the blockchain and they verify the transactions independently. Hence, this system allows transaction even if the parties don't trust each other.<br />
# Immutable: Once the transaction is verified and embedded in the blockchain, it is almost impossible to undo it, and the complexity increases with time as more blocks are added downstream. This allows keeping a track of accurate events that occurred through the history.<br />
# Decentralized: There is no middleman like banks or data owners. This helps avoid manipulation of the market by the owners.<br />
<br />
<br />
=== Cons: ===<br />
# Waste of resources: As several nodes are running and utilizing a huge amount of computing power and electricity to verify and maintain the blockchain, there is more than required redundancy. <br />
# Higher cost for less value: With time, the use of network increases and the complexity of the hashing algorithm also increases. Hence, more resources are required for the same amount of work. This increases the cost of work and transactions gets slower, as miners prioritize the transactions with higher incentives causing a backlog the transactions with smaller values. <br />
# Difficulty to keep up with the size of the block: As the size continues to grow along with the complexity to solve the calculation, new nodes with smaller computing power will have difficulty joining the network and likewise, the older and slower nodes will gradually fade with decreasing incentive for the work. Hence, like Darwin’s theory of the "survival of the fittest", a few larger nodes will dominate the network creating more and more centralization of the system. <br />
# Speculative market: Due to the lack of proper regulation of this system, the market is subject to a great volatility and thus making it risky for investors. <br />
# Immutable smart contracts: As there are clear advantages of having permanent and immutable records, at the same time, there is a bitter flipside to this. For example, if there is a flaw with code that can compromise the system, it is also irreparable and creates the opportunity for the attackers to exploit the same flaw repetitively in future. As time progresses, the capability of repairing the error will be even more complex.<br />
<br />
<br />
<br />
=== Possible Solutions: ===<br />
# The issues with resource wastefulness and diminishing return of investment are mainly an issue with Proof-of-Work Systems, and can be improved with new blockchain innovations such as [https://en.bitcoin.it/wiki/Proof_of_Stake Proof of Stake (Bitcoin Wiki)] or blockchain scaling<ref>Croman, Kyle, et al. "On scaling decentralized blockchains." International Conference on Financial Cryptography and Data Security. Springer, Berlin, Heidelberg, 2016.</ref><br />
** There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake<ref>Siim, Janno. "Proof-of-Stake."</ref>. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker.<br />
** Currently, all computers that participate in mining a blockchain process every transaction. This is very slow and resource wasteful. A solution to this is to calculate how many computers will be needed to validate a new block, and give the task of verifying a transaction to those computers. This will allow parallel processing and speed up transactions. At this point, the details behind how to manage this division of tasks without compromising security still being worked out.<br />
<br />
== Potential Use Cases in Healthcare ==<br />
Though there has yet to be a breakthrough report or use-case for blockchain technology in healthcare, there are many potential ways that the blockchain could be implemented within the current healthcare structure. Any list will likely be incomplete, but these examples represent some of the published and available literature on blockchain implementations in health.<br />
<br />
=== Health Information Exchange (HIE) ===<br />
One major area that blockchains may be able to facilitate is the secure access to and communication of patient health records between individuals and institutions. There have been multiple white papers published on the topic, including groups from the Mayo Clinic <ref>Peterson K, Deeduvanu R, Kanjamala P, Boles K. A Blockchain-Based Approach to Health Information Exchange Networks. (1):1–10.</ref> and MIT <ref>Ekblaw A, Azaria A, Halamka JD, Lippman A, Original I, Vieira T. A Case Study for Blockchain in Healthcare: “ MedRec ” prototype for electronic health records and medical research data MedRec: Using Blockchain for Medical Data Access and Permission Management [Internet]. 2016. Available from: https://www.healthit.gov/sites/default/files/5-56-onc_blockchainchallenge_mitwhitepaper.pdf</ref> who described a system for patient information exchange based on blockchain technology that would allow patient-controlled access to records across institutions using HL7 Fast Healthcare Interoperability Resources ([[FHIR]]), [http://json.org JSON], or other encoding system. In these models the actual health care data are not encoded in the blockchain, but are merely references pointing to where the data reside, such as at institutions or in a "data lake" <ref>Linn LA, Koo MB. Blockchain For Health Data and Its Potential Use in Health IT and Health Care Related Research. 2014;1–10.</ref>. Similarly, a group out of China described an app called Healthcare Data Gateway (HGD) that allows patients to view and directly control rule-based access to their health records with a smart phone interface and authentication provided by a blockchain network <ref>Yue X, Wang H, Jin D, Li M, Jiang W. Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst [Internet]. 2016 Oct;40(10):218. Available from: http://dx.doi.org/10.1007/s10916-016-0574-6</ref>. These ideas support the concept of patient-owned medical data, and would have the effect of decentralization of medical records in ways that are as yet undetermined.<br />
<br />
=== Health Research Integrity ===<br />
Academic research is a major driver of advances in health care, but in the setting of limited funding and publication pressures on researchers significant concerns have been raised regarding research integrity<ref>Titus SL, Wells J a, Rhoades LJ. Repairing research integrity. Nature [Internet]. 2008 Jun 19;453(7198):980–2. Available from: http://www.ncbi.nlm.nih.gov/pubmed/18563131</ref>. Organizations such as [http://clinicaltrials.gov ClinicalTrials.gov] and others have been developed to help drive researchers to define endpoints and analysis prior to conducting clinical trials and other studies. As it represents an immutable, verifiable record of events and transactions, the blockchain has been proposed as a potential decentralized resources for helping to ensure biomedical research integrity. Benjamin Carlisle<ref>Carlisle BG. Proof of prespecified endpoints in medical research with the bitcoin blockchain [Internet]. 2014. Available from: http://www.bgcarlisle.com/blog/2014/08/25/proof-of-prespecified-endpoints-in-medical-research-with-the-bitcoin-blockchain/</ref>, followed by several researchers from the UK<ref>Irving G, Holden J. How blockchain-timestamped protocols could improve the trustworthiness of medical science. F1000Research [Internet]. 2016;5:222. Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4866630/</ref>, proposed in 2014 that researchers could use the blockchain to record pre-specified aspects of their projects, including the study design, analysis plan, and data structure, among others, which could later be verified by consumers of the literature to decrease bias that may be introduced in post-hoc analysis<ref>Slade E, Drysdale H, Goldacre B, COMPare Team. Discrepancies Between Prespecified and Reported Outcomes. Ann Intern Med [Internet]. 2016 Mar 1;164(5):374. Available from: http://www.ncbi.nlm.nih.gov/pubmed/26720309</ref>. The blockchain also offers the potential ability to verify the integrity of actual research data and analysis by outside observers, even if the data themselves are not made publicly available. These types of implementations may lead to improvements in both the integrity of biomedical research as well as bolster public trust in medical research.<br />
<br />
=== Personal Health Records ===<br />
This concept dovetails with the idea of HIE using the blockchain, but focuses more on the secure maintenance of a personal health record (PHR) by patients. No production PHR has been released based on this technology, but concepts such as MedVault <ref>Baxendale G. Can Blockchain Revolutionise EPRs? [Internet]. Vol. 58, ITNOW. 2016. p. 38–9. Available from: http://itnow.oxfordjournals.org/lookup/doi/10.1093/itnow/bww017</ref> use alternative blockchains such as [http://www.Colu.com Colu] to store patient data directly on the blockchain. Others such as [https://devpost.com/software/ehealthwallet eHealthWallet] have also developed prototype PHRs based on the blockchain. Patients could then share or authorize doctors and other health entities to access and modify their data.<br />
<br />
The majority of the proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference<ref>Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230</ref><ref>Yue, X., Wang, H., Jin, D., Li, M., & Jiang, W. (2016). Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst, 40(10), 218. doi:10.1007/s10916-016-0574-6</ref>. <br />
* In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care.<br />
* As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed.<br />
* A blockchain-enabled smart contracts controlled by the patient can be used to authorize direct sharing of medical record between institutions. Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability<ref>Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230</ref>: <br />
* Digital access rules: The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application<br />
* Data aggregation: Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health<br />
* Data liquidity: Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc.<br />
* Patient identity: Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems<br />
* Data immutability: Since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time.<br />
<br />
=== Storage of Health Care Data ===<br />
Most of the previous examples use the blockchain not as a direct data storage medium, but instead as a secure reference point for identities, access, and data locations. At least one group from a company called Tierion, which partners with the [http://www.2.forms.healthcare.philips.com/blockchainlabs Philips Blockchain Lab ], has produced a concept called Chainpoint<ref>Vaughan AW, Bukowski J, Wilkinson S, Sporny CM, Shea R, Allen C, et al. Chainpoint: A scalable protocol for anchoring data in the blockchain and generating blockchain receipts [Internet]. 2016. Available from: https://tierion.com/chainpoint</ref>, which proposes to use a [https://proofofexistence.com/about Proof of Existence] concept and Merkle Roots<ref>Merkle RC. PROTOCOLS FOR PUBUC KEY CRYPTOSYSTEMS. In: IEEE Symposium on Security and Privacy [Internet]. 1980. p. 122–34. Available from: http://www.merkle.com/papers/Protocols.pdf</ref> to efficiently store actual patient records on the blockchain without imposing excessive transaction demands on the system.<br />
<br />
=== Billing and Claims Adjudication ===<br />
Blockchain system can help reduce administrative costs and time while automating claims adjudication and payment processing using smart contracts. For example - a smart contract is set up between payer or insurance company, provider, and patient such that when the patient sees a provider, or if a procedure is done, an entry is recorded in the blockchain. Based on the criteria set, the contract can automatically issue reimbursement from the payer as well as co-pay from the patient without having to wait for the insurance approval.<ref>Srinivasan, P. (2017, November 9). Healthcare Blockchain: How Smart Contracts Could Revolutionize Care Delivery. Prolifics. Retrieved from: https://www.prolifics.com/blog/healthcare-blockchain-how-smart-contracts-could-revolutionize-care-delivery</ref><br />
<br />
=== Drug Supply Chain and Prescription Management ===<br />
Counterfeit drugs are a major problem especially in the developing country where it is estimated that about 1 in 10 medical products are counterfeit <ref>WHO. (2017, November 28). 1 in 10 medical products in developing countries is substandard or falsified. Retrieved from: http://www.who.int/en/news-room/detail/28-11-2017-1-in-10-medical-products-in-developing-countries-is-substandard-or-falsified</ref>. Ensuring the integrity of the drug and maintaining a robust audit trail is a must to ensure patient safety. Similarly, this platform can be used in prescription drug management and track history and authenticate prescriptions using smart-contracts. <br />
<br />
=== Few Examples of Current Use Cases and Future Development ===<br />
<br />
* MedRec- it is based on Ethereum platform and focuses on medical data management using smart contracts like managing permissions and authentication processes, data sharing in an interoperable environment between healthcare systems and maintaining an audit log. <ref>Azaria, A., Ekblaw, A., Vieira, T., & Lippman, A. (2016, August 22-24). MedRec: Using Blockchain for Medical Data Access and Permission Management. 2016 2nd International Conference on Open and Big Data (OBD). doi:10.1109/obd.2016.11</ref><br />
<br />
* Guardtime- also focuses on medical data management and has partnered with e-Health authority of Estonia to secure the country's database of health records <ref>Ruubel M. (2016, February 12). Estonian eHealth Authority Partners with Guardtime to Accelerate Transparency and Auditability in Health Care. Retrieved from: https://guardtime.com/blog/estonian-ehealth-partners-guardtime-blockchain-based-transparency</ref>. Also, recently, MyPCR smartphone platform from Guardtime has partnered with Instant Access Medical and Healthcare Gateway in the UK for patient health data management and verification of medication adherence. <ref>Ruubel M. (2018, June 20). World’s first blockchain-supported Personal Care Record Platform launched by Guardtime and partners to up to 30 million NHS patients in the UK. Retrieved from: https://guardtime.com/blog/world-s-first-blockchain-supported-personal-care-record-platform-launched-by-guardtime-and-partners</ref> <br />
<br />
* Blockchain Health- created for healthcare research data management where users can individually authorize the release of their health information to researchers as well as track the use of their data. <ref>BlockchainHealth. (2016). Blockchain for health research. Retrieved from: https://blockchainhealth.co/</ref><br />
<br />
* BlockMedx- it is a startup company which intends to use the blockchain platform to transmit DEA controlled drug prescriptions from physicians to pharmacies and then to patients securely. <ref>BlockMedx. (2018). Retrieved from: https://blockmedx.com/en/</ref><br />
<br />
* MediLedger- another pharmaceutical supply chain management startup company who has partnered with several drug manufacturers and aims to provide an open, secure and interoperable network. <ref>MediLedger. (2018). The MediLedger Project. Retrieved from: https://mediledger.com/</ref><br />
<br />
* Drug and Pharmacy Verification - [https://devpost.com/software/veripharm VeriPharm] has developed a proof of concept that would help track and verify pharmaceuticals from the raw materials to the final product administered to patients.<br />
<br />
* Appointment Scheduling on the Blockchain - [https://devpost.com/software/dhva-appointment-blocks dhva-apointment-blocks]<br />
<br />
* Care Coordination - Projects such as [https://devpost.com/software/simplyvitahlth simplyvitahlth] are geared toward coordinating care between multiple providers and at different institutions to ensure that complex care pathways are being followed appropriately.<br />
<br />
<br />
There are many more potential use-cases for blockchain technology within healthcare, and undoubtedly we will continue to see development in this area in coming years. In 2016, a consortium of sponsors led by [https://gem.co/ Gem] (Whitepaper)<ref>Wood C, Winton B, Carter K, Benkert S, Dodd L, Bradley J, et al. How Blockchain Technology Can Enhance Ehr Operability [Internet]. 2016. Available from: http://research.ark-invest.com/blockchain-and-healthcare</ref> held the first healthcare oriented blockchain conference, [https://godistributed.com/health Distributed: Health] in Nashville, TN. Similarly, the Office of the National Coordinator (ONC) Tech Lab had issued a Blockchain Challenge in July, 2016.<ref>https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab</ref><br />
* The list of submissions and awards can be found [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab here]<br />
<br />
As the healthcare blockchain community grows, gatherings such as these will likely increase and blockchain technologies will increasingly be introduced at major medical conferences.<br />
<br />
== References ==<br />
<references /><br />
<br />
Submitted by Sandeep Regmi<br />
[[Category: BMI512-FALL-18]]<br />
<br />
Submitted by Ben Orwoll<br />
<br />
[[Category: BMI512-FALL-16]]<br />
[[Category: Reviews]]<br />
[[Category: Other Technologies]]</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/The_Blockchain_in_HealthcareThe Blockchain in Healthcare2018-10-19T03:06:06Z<p>Phamnh: /* What is the Blockchain? */</p>
<hr />
<div>The blockchain is an idea centered around the concept of a secure, digital ledger system that provides a system for efficient, auditable transactions of almost any type between entities <ref>Tapscott D, Tapscott A. Blockchain Revolution: How the Technology Behind Bitcoin Is Changing Money, Business, and the World. United States: Portfolio; 2016. 1-368 p.</ref>. All information related to blockchain transactions is at once both independently verifiable by all (even outside) parties as correct and also inscrutable to entities without explicit permission. The first and probably most well-known implementation of blockchain technology is [https://bitcoin.org Bitcoin] <ref name="BTC">Nakamoto S. Bitcoin: A Peer-to-Peer Electronic Cash System. WwwBitcoinOrg [Internet]. 2008;9. Available from: https://bitcoin.org/bitcoin.pdf</ref>, but there has been a massive expansion of blockchain use-cases since Bitcoin's initial introduction.<br />
<br />
<br />
<br />
== What is the Blockchain? ==<br />
<br />
First, it should be clear that there is no one blockchain to rule them all. "The Blockchain," as it is often referred, really is a concept of a series (chain) of interrelated sets (blocks) of encrypted information. Hence a chain of blocks, or blockchain. There are many such blockchains in existence, and one could choose to do transactions on any one of them or create a new blockchain.<br />
<br />
<br />
An important aspect of most blockchains is that they are designed to be maintained on a distributed network of multiple nodes. Each node holds a complete copy of the blockchain and adds each sequential new block as it is created. This system allows every transaction on the blockchain to be verified by any or all of the nodes in the network, and also makes it very difficult for the information held in the blockchain to become lost or unavailable if any one or even most of the nodes go offline.<br />
<br />
<br />
Transactions that are set to be added to the blockchain are added to the newest block as soon as it is created. This makes the continued existence of the blockchain dependent on the creation of new blocks. There are several main methods for the creation of new blocks on the network, and the choice of method depends somewhat on the purpose of the blockchain in question. Bitcoin, the first cryptocurrency, uses a method called [https://en.wikipedia.org/wiki/Proof-of-work_system Proof of Work System (Wikipedia)]:<br />
* In the traditional Proof of Work System, each block validator, or "miner," competes to validate the block by processing a task. The winner is the first person to complete this task. The chance of completion of the task is random based on a hash function, but increases with the more "work" a person puts into the task. The system can automatically vary the difficulty of the task to limit the speed of block generation. The winner is credited for his/her work by a small amount of currency. <br />
<br />
<br />
The blockchain has moved beyond simply processing transactions of cryptocurrency such as Bitcoin. Any data that can be encoded into a cryptographic [https://en.wikipedia.org/wiki/Hash_function hash] can be added to a blockchain. Various different ideas have been proposed, and I will not attempt to list them here, but they are wide ranging. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0<ref>Swan, M. (2015). Blockchain: Blueprint for a new economy: " O'Reilly Media, Inc."</ref>. Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education.<br />
<br />
<br />
=== Blockchain Development Groups ===<br />
Certainly a non-exhaustive list . . .<br />
<br />
* [https://bitcoin.org/en/ Bitcoin]<br />
<br />
* [https://hyperledger.org The Hyperledger Project]<br />
<br />
* [https://ethereum.org The Ethereum Project]<br />
<br />
* [https://r3cev.com/blog/2016/4/4/introducing-r3-corda-a-distributed-ledger-designed-for-financial-services The CORDA Platform]<br />
<br />
* [http://www.muskokagroup.org/ The Muskoka Group]<br />
<br />
* [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab The ONC Tech Lab]<br />
<br />
== Blockchain Use Cases ==<br />
<br />
=== Cryptocurrency ===<br />
Bitcoin (BTC) was the first cryptocurrency based on the blockchain and was developed by someone calling himself (or herself) Satoshi Nakamoto. The protocol was introduced in 2008 after the publication of a white paper<ref name="BTC" /> describing the algorithm and the mechanisms for generation and distribution of BTC. At this point there are hundreds of cryptocurrencies in circulation according to [http://wikipedia.org Wikipedia], many of which are based on the Bitcoin blockchain, but only a few have gone into widespread use<ref>https://en.wikipedia.org/wiki/List_of_cryptocurrencies</ref>.<br />
<br />
=== Smart Contracts ===<br />
One of the major potential functions of blockchain technology is through the creation of smart contracts. Various components of contracts, including proof of the involved parties, requirements for completion, and actions upon completion of the contract can be encoded in blocks. These can then be added to a blockchain and become available for independent verification, which can even lead to automatic processing of contracts when their requirements have been fulfilled.<br />
<br />
Smart contracts are scripts which have various rules and logic that automatically execute when those rules are met. Smart contracts allow heavily automated workflows between transacting parties in the network while maintaining anonymity. Once the contract has been executed, one can take custody over assets or pre-defined payments can be issued. <ref>Christidis, K & Devetsikiotis, M. (2016, May 10). Blockchains and Smart Contracts for the Internet of Things. IEEE Access, 4, 2292-2303. doi: 10.1109/ACCESS.2016.2566339</ref> They are importantly different in the sense that they are stored on a distributed network and they can be verified as true without knowledge of the contract specifications <ref>https://bitsonblocks.net/2016/02/01/a-gentle-introduction-to-smart-contracts/</ref>.<br />
<br />
[https://ethereum.org The Ethereum Project] was one of the first to introduce the concept of smart contracts using their alternative blockchain and currency token, [https://www.ethereum.org/ether ether].<br />
<br />
=== Securities Exchanges and Finance ===<br />
<br />
One of the hottest arenas for blockchain development currently is in the financial markets, an extension of the original cryptocurrency use cases for the blockchain. Multiple stock markets and other financial firms have initiated investigations and pilot projects into the feasibility and utility of the blockchain for contracts and tracking of financial instruments. NASDAQ has been one of the first major markets to put blockchain technology into use, and has released some information on its implementation, called Linq <ref>http://ir.nasdaq.com/releasedetail.cfm?releaseid=948326</ref><ref>http://www.coindesk.com/hands-on-with-linq-nasdaqs-private-markets-blockchain-project/</ref>. The cryptocurrency website [http://www.coindesk.com Coindesk] has also produced a list of 10 exchanges using or investigating blockchain technologies<ref>http://www.coindesk.com/10-stock-exchanges-blockchain/</ref>.<br />
<br />
<br />
Additionally, financial firms such as Visa have been experimenting with the blockchain for keeping track of transactions as well as with proof of concept applications such as remittance<ref>http://www.coindesk.com/hands-on-with-visa-europes-bitcoin-remittance-app/</ref>.<br />
<br />
== Advantages and Disadvantages of Blockchain ==<br />
<br />
Blockchain is a novel concept and is being explored in various sectors. While there may be several applications and limitations of this technology in future, some of them are highlighted below<ref>Fauvel, W. (2017, August 11). Blockchain Advantage and Disadvantages. Medium. Retrieved from: https://medium.com/nudjed/blockchain-advantage-and-disadvantages-e76dfde3bbc0</ref>:<br />
<br />
=== Pros: ===<br />
# Distributed: There is no single owner of the database. As anyone can contribute and be a part of the network, the risks of data tampering and fraud are minimal. As Nakamoto <ref name="BTC" /> mentioned, as long as the majority of nodes are honest, a random attacker would not be able to alter the history.<br />
# Trustless: As every node in the network will have a copy of the blockchain and they verify the transactions independently. Hence, this system allows transaction even if the parties don't trust each other.<br />
# Immutable: Once the transaction is verified and embedded in the blockchain, it is almost impossible to undo it, and the complexity increases with time as more blocks are added downstream. This allows keeping a track of accurate events that occurred through the history.<br />
# Decentralized: There is no middleman like banks or data owners. This helps avoid manipulation of the market by the owners.<br />
<br />
<br />
=== Cons: ===<br />
# Waste of resources: As several nodes are running and utilizing a huge amount of computing power and electricity to verify and maintain the blockchain, there is more than required redundancy. <br />
# Higher cost for less value: With time, the use of network increases and the complexity of the hashing algorithm also increases. Hence, more resources are required for the same amount of work. This increases the cost of work and transactions gets slower, as miners prioritize the transactions with higher incentives causing a backlog the transactions with smaller values. <br />
# Difficulty to keep up with the size of the block: As the size continues to grow along with the complexity to solve the calculation, new nodes with smaller computing power will have difficulty joining the network and likewise, the older and slower nodes will gradually fade with decreasing incentive for the work. Hence, like Darwin’s theory of the "survival of the fittest", a few larger nodes will dominate the network creating more and more centralization of the system. <br />
# Speculative market: Due to the lack of proper regulation of this system, the market is subject to a great volatility and thus making it risky for investors. <br />
# Immutable smart contracts: As there are clear advantages of having permanent and immutable records, at the same time, there is a bitter flipside to this. For example, if there is a flaw with code that can compromise the system, it is also irreparable and creates the opportunity for the attackers to exploit the same flaw repetitively in future. As time progresses, the capability of repairing the error will be even more complex.<br />
<br />
=== Possible Solutions: ===<br />
# The issues with resource waste and diminishing return of investment are mainly an issue with Proof-of-Work Systems, and can be improved with new blockchain innovations such as Proof-of-Stake or blockchain scaling.<br />
<br />
== Potential Use Cases in Healthcare ==<br />
Though there has yet to be a breakthrough report or use-case for blockchain technology in healthcare, there are many potential ways that the blockchain could be implemented within the current healthcare structure. Any list will likely be incomplete, but these examples represent some of the published and available literature on blockchain implementations in health.<br />
<br />
=== Health Information Exchange (HIE) ===<br />
One major area that blockchains may be able to facilitate is the secure access to and communication of patient health records between individuals and institutions. There have been multiple white papers published on the topic, including groups from the Mayo Clinic <ref>Peterson K, Deeduvanu R, Kanjamala P, Boles K. A Blockchain-Based Approach to Health Information Exchange Networks. (1):1–10.</ref> and MIT <ref>Ekblaw A, Azaria A, Halamka JD, Lippman A, Original I, Vieira T. A Case Study for Blockchain in Healthcare: “ MedRec ” prototype for electronic health records and medical research data MedRec: Using Blockchain for Medical Data Access and Permission Management [Internet]. 2016. Available from: https://www.healthit.gov/sites/default/files/5-56-onc_blockchainchallenge_mitwhitepaper.pdf</ref> who described a system for patient information exchange based on blockchain technology that would allow patient-controlled access to records across institutions using HL7 Fast Healthcare Interoperability Resources ([[FHIR]]), [http://json.org JSON], or other encoding system. In these models the actual health care data are not encoded in the blockchain, but are merely references pointing to where the data reside, such as at institutions or in a "data lake" <ref>Linn LA, Koo MB. Blockchain For Health Data and Its Potential Use in Health IT and Health Care Related Research. 2014;1–10.</ref>. Similarly, a group out of China described an app called Healthcare Data Gateway (HGD) that allows patients to view and directly control rule-based access to their health records with a smart phone interface and authentication provided by a blockchain network <ref>Yue X, Wang H, Jin D, Li M, Jiang W. Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst [Internet]. 2016 Oct;40(10):218. Available from: http://dx.doi.org/10.1007/s10916-016-0574-6</ref>. These ideas support the concept of patient-owned medical data, and would have the effect of decentralization of medical records in ways that are as yet undetermined.<br />
<br />
=== Health Research Integrity ===<br />
Academic research is a major driver of advances in health care, but in the setting of limited funding and publication pressures on researchers significant concerns have been raised regarding research integrity<ref>Titus SL, Wells J a, Rhoades LJ. Repairing research integrity. Nature [Internet]. 2008 Jun 19;453(7198):980–2. Available from: http://www.ncbi.nlm.nih.gov/pubmed/18563131</ref>. Organizations such as [http://clinicaltrials.gov ClinicalTrials.gov] and others have been developed to help drive researchers to define endpoints and analysis prior to conducting clinical trials and other studies. As it represents an immutable, verifiable record of events and transactions, the blockchain has been proposed as a potential decentralized resources for helping to ensure biomedical research integrity. Benjamin Carlisle<ref>Carlisle BG. Proof of prespecified endpoints in medical research with the bitcoin blockchain [Internet]. 2014. Available from: http://www.bgcarlisle.com/blog/2014/08/25/proof-of-prespecified-endpoints-in-medical-research-with-the-bitcoin-blockchain/</ref>, followed by several researchers from the UK<ref>Irving G, Holden J. How blockchain-timestamped protocols could improve the trustworthiness of medical science. F1000Research [Internet]. 2016;5:222. Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4866630/</ref>, proposed in 2014 that researchers could use the blockchain to record pre-specified aspects of their projects, including the study design, analysis plan, and data structure, among others, which could later be verified by consumers of the literature to decrease bias that may be introduced in post-hoc analysis<ref>Slade E, Drysdale H, Goldacre B, COMPare Team. Discrepancies Between Prespecified and Reported Outcomes. Ann Intern Med [Internet]. 2016 Mar 1;164(5):374. Available from: http://www.ncbi.nlm.nih.gov/pubmed/26720309</ref>. The blockchain also offers the potential ability to verify the integrity of actual research data and analysis by outside observers, even if the data themselves are not made publicly available. These types of implementations may lead to improvements in both the integrity of biomedical research as well as bolster public trust in medical research.<br />
<br />
=== Personal Health Records ===<br />
This concept dovetails with the idea of HIE using the blockchain, but focuses more on the secure maintenance of a personal health record (PHR) by patients. No production PHR has been released based on this technology, but concepts such as MedVault <ref>Baxendale G. Can Blockchain Revolutionise EPRs? [Internet]. Vol. 58, ITNOW. 2016. p. 38–9. Available from: http://itnow.oxfordjournals.org/lookup/doi/10.1093/itnow/bww017</ref> use alternative blockchains such as [http://www.Colu.com Colu] to store patient data directly on the blockchain. Others such as [https://devpost.com/software/ehealthwallet eHealthWallet] have also developed prototype PHRs based on the blockchain. Patients could then share or authorize doctors and other health entities to access and modify their data.<br />
<br />
The majority of the proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference<ref>Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230</ref><ref>Yue, X., Wang, H., Jin, D., Li, M., & Jiang, W. (2016). Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst, 40(10), 218. doi:10.1007/s10916-016-0574-6</ref>. <br />
* In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care.<br />
* As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed.<br />
* A blockchain-enabled smart contracts controlled by the patient can be used to authorize direct sharing of medical record between institutions. Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability<ref>Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230</ref>: <br />
* Digital access rules: The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application<br />
* Data aggregation: Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health<br />
* Data liquidity: Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc.<br />
* Patient identity: Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems<br />
* Data immutability: Since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time.<br />
<br />
=== Storage of Health Care Data ===<br />
Most of the previous examples use the blockchain not as a direct data storage medium, but instead as a secure reference point for identities, access, and data locations. At least one group from a company called Tierion, which partners with the [http://www.2.forms.healthcare.philips.com/blockchainlabs Philips Blockchain Lab ], has produced a concept called Chainpoint<ref>Vaughan AW, Bukowski J, Wilkinson S, Sporny CM, Shea R, Allen C, et al. Chainpoint: A scalable protocol for anchoring data in the blockchain and generating blockchain receipts [Internet]. 2016. Available from: https://tierion.com/chainpoint</ref>, which proposes to use a [https://proofofexistence.com/about Proof of Existence] concept and Merkle Roots<ref>Merkle RC. PROTOCOLS FOR PUBUC KEY CRYPTOSYSTEMS. In: IEEE Symposium on Security and Privacy [Internet]. 1980. p. 122–34. Available from: http://www.merkle.com/papers/Protocols.pdf</ref> to efficiently store actual patient records on the blockchain without imposing excessive transaction demands on the system.<br />
<br />
=== Billing and Claims Adjudication ===<br />
Blockchain system can help reduce administrative costs and time while automating claims adjudication and payment processing using smart contracts. For example - a smart contract is set up between payer or insurance company, provider, and patient such that when the patient sees a provider, or if a procedure is done, an entry is recorded in the blockchain. Based on the criteria set, the contract can automatically issue reimbursement from the payer as well as co-pay from the patient without having to wait for the insurance approval.<ref>Srinivasan, P. (2017, November 9). Healthcare Blockchain: How Smart Contracts Could Revolutionize Care Delivery. Prolifics. Retrieved from: https://www.prolifics.com/blog/healthcare-blockchain-how-smart-contracts-could-revolutionize-care-delivery</ref><br />
<br />
=== Drug Supply Chain and Prescription Management ===<br />
Counterfeit drugs are a major problem especially in the developing country where it is estimated that about 1 in 10 medical products are counterfeit <ref>WHO. (2017, November 28). 1 in 10 medical products in developing countries is substandard or falsified. Retrieved from: http://www.who.int/en/news-room/detail/28-11-2017-1-in-10-medical-products-in-developing-countries-is-substandard-or-falsified</ref>. Ensuring the integrity of the drug and maintaining a robust audit trail is a must to ensure patient safety. Similarly, this platform can be used in prescription drug management and track history and authenticate prescriptions using smart-contracts. <br />
<br />
=== Few Examples of Current Use Cases and Future Development ===<br />
<br />
* MedRec- it is based on Ethereum platform and focuses on medical data management using smart contracts like managing permissions and authentication processes, data sharing in an interoperable environment between healthcare systems and maintaining an audit log. <ref>Azaria, A., Ekblaw, A., Vieira, T., & Lippman, A. (2016, August 22-24). MedRec: Using Blockchain for Medical Data Access and Permission Management. 2016 2nd International Conference on Open and Big Data (OBD). doi:10.1109/obd.2016.11</ref><br />
<br />
* Guardtime- also focuses on medical data management and has partnered with e-Health authority of Estonia to secure the country's database of health records <ref>Ruubel M. (2016, February 12). Estonian eHealth Authority Partners with Guardtime to Accelerate Transparency and Auditability in Health Care. Retrieved from: https://guardtime.com/blog/estonian-ehealth-partners-guardtime-blockchain-based-transparency</ref>. Also, recently, MyPCR smartphone platform from Guardtime has partnered with Instant Access Medical and Healthcare Gateway in the UK for patient health data management and verification of medication adherence. <ref>Ruubel M. (2018, June 20). World’s first blockchain-supported Personal Care Record Platform launched by Guardtime and partners to up to 30 million NHS patients in the UK. Retrieved from: https://guardtime.com/blog/world-s-first-blockchain-supported-personal-care-record-platform-launched-by-guardtime-and-partners</ref> <br />
<br />
* Blockchain Health- created for healthcare research data management where users can individually authorize the release of their health information to researchers as well as track the use of their data. <ref>BlockchainHealth. (2016). Blockchain for health research. Retrieved from: https://blockchainhealth.co/</ref><br />
<br />
* BlockMedx- it is a startup company which intends to use the blockchain platform to transmit DEA controlled drug prescriptions from physicians to pharmacies and then to patients securely. <ref>BlockMedx. (2018). Retrieved from: https://blockmedx.com/en/</ref><br />
<br />
* MediLedger- another pharmaceutical supply chain management startup company who has partnered with several drug manufacturers and aims to provide an open, secure and interoperable network. <ref>MediLedger. (2018). The MediLedger Project. Retrieved from: https://mediledger.com/</ref><br />
<br />
* Drug and Pharmacy Verification - [https://devpost.com/software/veripharm VeriPharm] has developed a proof of concept that would help track and verify pharmaceuticals from the raw materials to the final product administered to patients.<br />
<br />
* Appointment Scheduling on the Blockchain - [https://devpost.com/software/dhva-appointment-blocks dhva-apointment-blocks]<br />
<br />
* Care Coordination - Projects such as [https://devpost.com/software/simplyvitahlth simplyvitahlth] are geared toward coordinating care between multiple providers and at different institutions to ensure that complex care pathways are being followed appropriately.<br />
<br />
<br />
There are many more potential use-cases for blockchain technology within healthcare, and undoubtedly we will continue to see development in this area in coming years. In 2016, a consortium of sponsors led by [https://gem.co/ Gem] (Whitepaper)<ref>Wood C, Winton B, Carter K, Benkert S, Dodd L, Bradley J, et al. How Blockchain Technology Can Enhance Ehr Operability [Internet]. 2016. Available from: http://research.ark-invest.com/blockchain-and-healthcare</ref> held the first healthcare oriented blockchain conference, [https://godistributed.com/health Distributed: Health] in Nashville, TN. Similarly, the Office of the National Coordinator (ONC) Tech Lab had issued a Blockchain Challenge in July, 2016.<ref>https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab</ref><br />
* The list of submissions and awards can be found [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab here]<br />
<br />
As the healthcare blockchain community grows, gatherings such as these will likely increase and blockchain technologies will increasingly be introduced at major medical conferences.<br />
<br />
== References ==<br />
<references /><br />
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Submitted by Sandeep Regmi<br />
[[Category: BMI512-FALL-18]]<br />
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Submitted by Ben Orwoll<br />
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[[Category: BMI512-FALL-16]]<br />
[[Category: Reviews]]<br />
[[Category: Other Technologies]]</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/The_Blockchain_in_HealthcareThe Blockchain in Healthcare2018-10-19T03:04:31Z<p>Phamnh: /* Cons: */</p>
<hr />
<div>The blockchain is an idea centered around the concept of a secure, digital ledger system that provides a system for efficient, auditable transactions of almost any type between entities <ref>Tapscott D, Tapscott A. Blockchain Revolution: How the Technology Behind Bitcoin Is Changing Money, Business, and the World. United States: Portfolio; 2016. 1-368 p.</ref>. All information related to blockchain transactions is at once both independently verifiable by all (even outside) parties as correct and also inscrutable to entities without explicit permission. The first and probably most well-known implementation of blockchain technology is [https://bitcoin.org Bitcoin] <ref name="BTC">Nakamoto S. Bitcoin: A Peer-to-Peer Electronic Cash System. WwwBitcoinOrg [Internet]. 2008;9. Available from: https://bitcoin.org/bitcoin.pdf</ref>, but there has been a massive expansion of blockchain use-cases since Bitcoin's initial introduction.<br />
<br />
<br />
<br />
== What is the Blockchain? ==<br />
<br />
First, it should be clear that there is no one blockchain to rule them all. "The Blockchain," as it is often referred, really is a concept of a series (chain) of interrelated sets (blocks) of encrypted information. Hence a chain of blocks, or blockchain. There are many such blockchains in existence, and one could choose to do transactions on any one of them or create a new blockchain.<br />
<br />
<br />
An important aspect of most blockchains is that they are designed to be maintained on a distributed network of multiple nodes. Each node holds a complete copy of the blockchain and adds each sequential new block as it is created. This system allows every transaction on the blockchain to be verified by any or all of the nodes in the network, and also makes it very difficult for the information held in the blockchain to become lost or unavailable if any one or even most of the nodes go offline.<br />
<br />
<br />
Transactions that are set to be added to the blockchain are added to the newest block as soon as it is created. This makes the continued existence of the blockchain dependent on the creation of new blocks. There are several main methods for the creation of new blocks on the network, and the choice of method depends somewhat on the purpose of the blockchain in question. Bitcoin, the first cryptocurrency, uses a method called Proof of Work, but there are at least two methods currently in use:<br />
* [https://en.wikipedia.org/wiki/Proof-of-work_system Proof of Work System (Wikipedia)]<br />
** In the traditional Proof of Work System, each block validator, or "miner," competes to validate the block by processing a task. The winner is the first person to complete this task. The chance of completion of the task is random based on a hash function, but increases with the more "work" a person puts into the task. The system can automatically vary the difficulty of the task to limit the speed of block generation. The winner is credited for his/her work by a small amount of currency. <br />
* [https://en.wikipedia.org/wiki/Proof-of-stake Proof of Stake (Wikipedia)] [https://en.bitcoin.it/wiki/Proof_of_Stake Proof of Stake (Bitcoin Wiki)]<br />
** There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake<ref>Siim, Janno. "Proof-of-Stake."</ref>. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker.<br />
<br />
<br />
The blockchain has moved beyond simply processing transactions of cryptocurrency such as Bitcoin. Any data that can be encoded into a cryptographic [https://en.wikipedia.org/wiki/Hash_function hash] can be added to a blockchain. Various different ideas have been proposed, and I will not attempt to list them here, but they are wide ranging. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0<ref>Swan, M. (2015). Blockchain: Blueprint for a new economy: " O'Reilly Media, Inc."</ref>. Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education.<br />
<br />
<br />
=== Blockchain Development Groups ===<br />
Certainly a non-exhaustive list . . .<br />
<br />
* [https://bitcoin.org/en/ Bitcoin]<br />
<br />
* [https://hyperledger.org The Hyperledger Project]<br />
<br />
* [https://ethereum.org The Ethereum Project]<br />
<br />
* [https://r3cev.com/blog/2016/4/4/introducing-r3-corda-a-distributed-ledger-designed-for-financial-services The CORDA Platform]<br />
<br />
* [http://www.muskokagroup.org/ The Muskoka Group]<br />
<br />
* [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab The ONC Tech Lab]<br />
<br />
== Blockchain Use Cases ==<br />
<br />
=== Cryptocurrency ===<br />
Bitcoin (BTC) was the first cryptocurrency based on the blockchain and was developed by someone calling himself (or herself) Satoshi Nakamoto. The protocol was introduced in 2008 after the publication of a white paper<ref name="BTC" /> describing the algorithm and the mechanisms for generation and distribution of BTC. At this point there are hundreds of cryptocurrencies in circulation according to [http://wikipedia.org Wikipedia], many of which are based on the Bitcoin blockchain, but only a few have gone into widespread use<ref>https://en.wikipedia.org/wiki/List_of_cryptocurrencies</ref>.<br />
<br />
=== Smart Contracts ===<br />
One of the major potential functions of blockchain technology is through the creation of smart contracts. Various components of contracts, including proof of the involved parties, requirements for completion, and actions upon completion of the contract can be encoded in blocks. These can then be added to a blockchain and become available for independent verification, which can even lead to automatic processing of contracts when their requirements have been fulfilled.<br />
<br />
Smart contracts are scripts which have various rules and logic that automatically execute when those rules are met. Smart contracts allow heavily automated workflows between transacting parties in the network while maintaining anonymity. Once the contract has been executed, one can take custody over assets or pre-defined payments can be issued. <ref>Christidis, K & Devetsikiotis, M. (2016, May 10). Blockchains and Smart Contracts for the Internet of Things. IEEE Access, 4, 2292-2303. doi: 10.1109/ACCESS.2016.2566339</ref> They are importantly different in the sense that they are stored on a distributed network and they can be verified as true without knowledge of the contract specifications <ref>https://bitsonblocks.net/2016/02/01/a-gentle-introduction-to-smart-contracts/</ref>.<br />
<br />
[https://ethereum.org The Ethereum Project] was one of the first to introduce the concept of smart contracts using their alternative blockchain and currency token, [https://www.ethereum.org/ether ether].<br />
<br />
=== Securities Exchanges and Finance ===<br />
<br />
One of the hottest arenas for blockchain development currently is in the financial markets, an extension of the original cryptocurrency use cases for the blockchain. Multiple stock markets and other financial firms have initiated investigations and pilot projects into the feasibility and utility of the blockchain for contracts and tracking of financial instruments. NASDAQ has been one of the first major markets to put blockchain technology into use, and has released some information on its implementation, called Linq <ref>http://ir.nasdaq.com/releasedetail.cfm?releaseid=948326</ref><ref>http://www.coindesk.com/hands-on-with-linq-nasdaqs-private-markets-blockchain-project/</ref>. The cryptocurrency website [http://www.coindesk.com Coindesk] has also produced a list of 10 exchanges using or investigating blockchain technologies<ref>http://www.coindesk.com/10-stock-exchanges-blockchain/</ref>.<br />
<br />
<br />
Additionally, financial firms such as Visa have been experimenting with the blockchain for keeping track of transactions as well as with proof of concept applications such as remittance<ref>http://www.coindesk.com/hands-on-with-visa-europes-bitcoin-remittance-app/</ref>.<br />
<br />
== Advantages and Disadvantages of Blockchain ==<br />
<br />
Blockchain is a novel concept and is being explored in various sectors. While there may be several applications and limitations of this technology in future, some of them are highlighted below<ref>Fauvel, W. (2017, August 11). Blockchain Advantage and Disadvantages. Medium. Retrieved from: https://medium.com/nudjed/blockchain-advantage-and-disadvantages-e76dfde3bbc0</ref>:<br />
<br />
=== Pros: ===<br />
# Distributed: There is no single owner of the database. As anyone can contribute and be a part of the network, the risks of data tampering and fraud are minimal. As Nakamoto <ref name="BTC" /> mentioned, as long as the majority of nodes are honest, a random attacker would not be able to alter the history.<br />
# Trustless: As every node in the network will have a copy of the blockchain and they verify the transactions independently. Hence, this system allows transaction even if the parties don't trust each other.<br />
# Immutable: Once the transaction is verified and embedded in the blockchain, it is almost impossible to undo it, and the complexity increases with time as more blocks are added downstream. This allows keeping a track of accurate events that occurred through the history.<br />
# Decentralized: There is no middleman like banks or data owners. This helps avoid manipulation of the market by the owners.<br />
<br />
<br />
=== Cons: ===<br />
# Waste of resources: As several nodes are running and utilizing a huge amount of computing power and electricity to verify and maintain the blockchain, there is more than required redundancy. <br />
# Higher cost for less value: With time, the use of network increases and the complexity of the hashing algorithm also increases. Hence, more resources are required for the same amount of work. This increases the cost of work and transactions gets slower, as miners prioritize the transactions with higher incentives causing a backlog the transactions with smaller values. <br />
# Difficulty to keep up with the size of the block: As the size continues to grow along with the complexity to solve the calculation, new nodes with smaller computing power will have difficulty joining the network and likewise, the older and slower nodes will gradually fade with decreasing incentive for the work. Hence, like Darwin’s theory of the "survival of the fittest", a few larger nodes will dominate the network creating more and more centralization of the system. <br />
# Speculative market: Due to the lack of proper regulation of this system, the market is subject to a great volatility and thus making it risky for investors. <br />
# Immutable smart contracts: As there are clear advantages of having permanent and immutable records, at the same time, there is a bitter flipside to this. For example, if there is a flaw with code that can compromise the system, it is also irreparable and creates the opportunity for the attackers to exploit the same flaw repetitively in future. As time progresses, the capability of repairing the error will be even more complex.<br />
<br />
=== Possible Solutions: ===<br />
# The issues with resource waste and diminishing return of investment are mainly an issue with Proof-of-Work Systems, and can be improved with new blockchain innovations such as Proof-of-Stake or blockchain scaling.<br />
<br />
== Potential Use Cases in Healthcare ==<br />
Though there has yet to be a breakthrough report or use-case for blockchain technology in healthcare, there are many potential ways that the blockchain could be implemented within the current healthcare structure. Any list will likely be incomplete, but these examples represent some of the published and available literature on blockchain implementations in health.<br />
<br />
=== Health Information Exchange (HIE) ===<br />
One major area that blockchains may be able to facilitate is the secure access to and communication of patient health records between individuals and institutions. There have been multiple white papers published on the topic, including groups from the Mayo Clinic <ref>Peterson K, Deeduvanu R, Kanjamala P, Boles K. A Blockchain-Based Approach to Health Information Exchange Networks. (1):1–10.</ref> and MIT <ref>Ekblaw A, Azaria A, Halamka JD, Lippman A, Original I, Vieira T. A Case Study for Blockchain in Healthcare: “ MedRec ” prototype for electronic health records and medical research data MedRec: Using Blockchain for Medical Data Access and Permission Management [Internet]. 2016. Available from: https://www.healthit.gov/sites/default/files/5-56-onc_blockchainchallenge_mitwhitepaper.pdf</ref> who described a system for patient information exchange based on blockchain technology that would allow patient-controlled access to records across institutions using HL7 Fast Healthcare Interoperability Resources ([[FHIR]]), [http://json.org JSON], or other encoding system. In these models the actual health care data are not encoded in the blockchain, but are merely references pointing to where the data reside, such as at institutions or in a "data lake" <ref>Linn LA, Koo MB. Blockchain For Health Data and Its Potential Use in Health IT and Health Care Related Research. 2014;1–10.</ref>. Similarly, a group out of China described an app called Healthcare Data Gateway (HGD) that allows patients to view and directly control rule-based access to their health records with a smart phone interface and authentication provided by a blockchain network <ref>Yue X, Wang H, Jin D, Li M, Jiang W. Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst [Internet]. 2016 Oct;40(10):218. Available from: http://dx.doi.org/10.1007/s10916-016-0574-6</ref>. These ideas support the concept of patient-owned medical data, and would have the effect of decentralization of medical records in ways that are as yet undetermined.<br />
<br />
=== Health Research Integrity ===<br />
Academic research is a major driver of advances in health care, but in the setting of limited funding and publication pressures on researchers significant concerns have been raised regarding research integrity<ref>Titus SL, Wells J a, Rhoades LJ. Repairing research integrity. Nature [Internet]. 2008 Jun 19;453(7198):980–2. Available from: http://www.ncbi.nlm.nih.gov/pubmed/18563131</ref>. Organizations such as [http://clinicaltrials.gov ClinicalTrials.gov] and others have been developed to help drive researchers to define endpoints and analysis prior to conducting clinical trials and other studies. As it represents an immutable, verifiable record of events and transactions, the blockchain has been proposed as a potential decentralized resources for helping to ensure biomedical research integrity. Benjamin Carlisle<ref>Carlisle BG. Proof of prespecified endpoints in medical research with the bitcoin blockchain [Internet]. 2014. Available from: http://www.bgcarlisle.com/blog/2014/08/25/proof-of-prespecified-endpoints-in-medical-research-with-the-bitcoin-blockchain/</ref>, followed by several researchers from the UK<ref>Irving G, Holden J. How blockchain-timestamped protocols could improve the trustworthiness of medical science. F1000Research [Internet]. 2016;5:222. Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4866630/</ref>, proposed in 2014 that researchers could use the blockchain to record pre-specified aspects of their projects, including the study design, analysis plan, and data structure, among others, which could later be verified by consumers of the literature to decrease bias that may be introduced in post-hoc analysis<ref>Slade E, Drysdale H, Goldacre B, COMPare Team. Discrepancies Between Prespecified and Reported Outcomes. Ann Intern Med [Internet]. 2016 Mar 1;164(5):374. Available from: http://www.ncbi.nlm.nih.gov/pubmed/26720309</ref>. The blockchain also offers the potential ability to verify the integrity of actual research data and analysis by outside observers, even if the data themselves are not made publicly available. These types of implementations may lead to improvements in both the integrity of biomedical research as well as bolster public trust in medical research.<br />
<br />
=== Personal Health Records ===<br />
This concept dovetails with the idea of HIE using the blockchain, but focuses more on the secure maintenance of a personal health record (PHR) by patients. No production PHR has been released based on this technology, but concepts such as MedVault <ref>Baxendale G. Can Blockchain Revolutionise EPRs? [Internet]. Vol. 58, ITNOW. 2016. p. 38–9. Available from: http://itnow.oxfordjournals.org/lookup/doi/10.1093/itnow/bww017</ref> use alternative blockchains such as [http://www.Colu.com Colu] to store patient data directly on the blockchain. Others such as [https://devpost.com/software/ehealthwallet eHealthWallet] have also developed prototype PHRs based on the blockchain. Patients could then share or authorize doctors and other health entities to access and modify their data.<br />
<br />
The majority of the proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference<ref>Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230</ref><ref>Yue, X., Wang, H., Jin, D., Li, M., & Jiang, W. (2016). Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst, 40(10), 218. doi:10.1007/s10916-016-0574-6</ref>. <br />
* In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care.<br />
* As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed.<br />
* A blockchain-enabled smart contracts controlled by the patient can be used to authorize direct sharing of medical record between institutions. Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability<ref>Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230</ref>: <br />
* Digital access rules: The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application<br />
* Data aggregation: Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health<br />
* Data liquidity: Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc.<br />
* Patient identity: Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems<br />
* Data immutability: Since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time.<br />
<br />
=== Storage of Health Care Data ===<br />
Most of the previous examples use the blockchain not as a direct data storage medium, but instead as a secure reference point for identities, access, and data locations. At least one group from a company called Tierion, which partners with the [http://www.2.forms.healthcare.philips.com/blockchainlabs Philips Blockchain Lab ], has produced a concept called Chainpoint<ref>Vaughan AW, Bukowski J, Wilkinson S, Sporny CM, Shea R, Allen C, et al. Chainpoint: A scalable protocol for anchoring data in the blockchain and generating blockchain receipts [Internet]. 2016. Available from: https://tierion.com/chainpoint</ref>, which proposes to use a [https://proofofexistence.com/about Proof of Existence] concept and Merkle Roots<ref>Merkle RC. PROTOCOLS FOR PUBUC KEY CRYPTOSYSTEMS. In: IEEE Symposium on Security and Privacy [Internet]. 1980. p. 122–34. Available from: http://www.merkle.com/papers/Protocols.pdf</ref> to efficiently store actual patient records on the blockchain without imposing excessive transaction demands on the system.<br />
<br />
=== Billing and Claims Adjudication ===<br />
Blockchain system can help reduce administrative costs and time while automating claims adjudication and payment processing using smart contracts. For example - a smart contract is set up between payer or insurance company, provider, and patient such that when the patient sees a provider, or if a procedure is done, an entry is recorded in the blockchain. Based on the criteria set, the contract can automatically issue reimbursement from the payer as well as co-pay from the patient without having to wait for the insurance approval.<ref>Srinivasan, P. (2017, November 9). Healthcare Blockchain: How Smart Contracts Could Revolutionize Care Delivery. Prolifics. Retrieved from: https://www.prolifics.com/blog/healthcare-blockchain-how-smart-contracts-could-revolutionize-care-delivery</ref><br />
<br />
=== Drug Supply Chain and Prescription Management ===<br />
Counterfeit drugs are a major problem especially in the developing country where it is estimated that about 1 in 10 medical products are counterfeit <ref>WHO. (2017, November 28). 1 in 10 medical products in developing countries is substandard or falsified. Retrieved from: http://www.who.int/en/news-room/detail/28-11-2017-1-in-10-medical-products-in-developing-countries-is-substandard-or-falsified</ref>. Ensuring the integrity of the drug and maintaining a robust audit trail is a must to ensure patient safety. Similarly, this platform can be used in prescription drug management and track history and authenticate prescriptions using smart-contracts. <br />
<br />
=== Few Examples of Current Use Cases and Future Development ===<br />
<br />
* MedRec- it is based on Ethereum platform and focuses on medical data management using smart contracts like managing permissions and authentication processes, data sharing in an interoperable environment between healthcare systems and maintaining an audit log. <ref>Azaria, A., Ekblaw, A., Vieira, T., & Lippman, A. (2016, August 22-24). MedRec: Using Blockchain for Medical Data Access and Permission Management. 2016 2nd International Conference on Open and Big Data (OBD). doi:10.1109/obd.2016.11</ref><br />
<br />
* Guardtime- also focuses on medical data management and has partnered with e-Health authority of Estonia to secure the country's database of health records <ref>Ruubel M. (2016, February 12). Estonian eHealth Authority Partners with Guardtime to Accelerate Transparency and Auditability in Health Care. Retrieved from: https://guardtime.com/blog/estonian-ehealth-partners-guardtime-blockchain-based-transparency</ref>. Also, recently, MyPCR smartphone platform from Guardtime has partnered with Instant Access Medical and Healthcare Gateway in the UK for patient health data management and verification of medication adherence. <ref>Ruubel M. (2018, June 20). World’s first blockchain-supported Personal Care Record Platform launched by Guardtime and partners to up to 30 million NHS patients in the UK. Retrieved from: https://guardtime.com/blog/world-s-first-blockchain-supported-personal-care-record-platform-launched-by-guardtime-and-partners</ref> <br />
<br />
* Blockchain Health- created for healthcare research data management where users can individually authorize the release of their health information to researchers as well as track the use of their data. <ref>BlockchainHealth. (2016). Blockchain for health research. Retrieved from: https://blockchainhealth.co/</ref><br />
<br />
* BlockMedx- it is a startup company which intends to use the blockchain platform to transmit DEA controlled drug prescriptions from physicians to pharmacies and then to patients securely. <ref>BlockMedx. (2018). Retrieved from: https://blockmedx.com/en/</ref><br />
<br />
* MediLedger- another pharmaceutical supply chain management startup company who has partnered with several drug manufacturers and aims to provide an open, secure and interoperable network. <ref>MediLedger. (2018). The MediLedger Project. Retrieved from: https://mediledger.com/</ref><br />
<br />
* Drug and Pharmacy Verification - [https://devpost.com/software/veripharm VeriPharm] has developed a proof of concept that would help track and verify pharmaceuticals from the raw materials to the final product administered to patients.<br />
<br />
* Appointment Scheduling on the Blockchain - [https://devpost.com/software/dhva-appointment-blocks dhva-apointment-blocks]<br />
<br />
* Care Coordination - Projects such as [https://devpost.com/software/simplyvitahlth simplyvitahlth] are geared toward coordinating care between multiple providers and at different institutions to ensure that complex care pathways are being followed appropriately.<br />
<br />
<br />
There are many more potential use-cases for blockchain technology within healthcare, and undoubtedly we will continue to see development in this area in coming years. In 2016, a consortium of sponsors led by [https://gem.co/ Gem] (Whitepaper)<ref>Wood C, Winton B, Carter K, Benkert S, Dodd L, Bradley J, et al. How Blockchain Technology Can Enhance Ehr Operability [Internet]. 2016. Available from: http://research.ark-invest.com/blockchain-and-healthcare</ref> held the first healthcare oriented blockchain conference, [https://godistributed.com/health Distributed: Health] in Nashville, TN. Similarly, the Office of the National Coordinator (ONC) Tech Lab had issued a Blockchain Challenge in July, 2016.<ref>https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab</ref><br />
* The list of submissions and awards can be found [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab here]<br />
<br />
As the healthcare blockchain community grows, gatherings such as these will likely increase and blockchain technologies will increasingly be introduced at major medical conferences.<br />
<br />
== References ==<br />
<references /><br />
<br />
Submitted by Sandeep Regmi<br />
[[Category: BMI512-FALL-18]]<br />
<br />
Submitted by Ben Orwoll<br />
<br />
[[Category: BMI512-FALL-16]]<br />
[[Category: Reviews]]<br />
[[Category: Other Technologies]]</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/The_Blockchain_in_HealthcareThe Blockchain in Healthcare2018-10-19T02:55:26Z<p>Phamnh: /* Personal Health Records */</p>
<hr />
<div>The blockchain is an idea centered around the concept of a secure, digital ledger system that provides a system for efficient, auditable transactions of almost any type between entities <ref>Tapscott D, Tapscott A. Blockchain Revolution: How the Technology Behind Bitcoin Is Changing Money, Business, and the World. United States: Portfolio; 2016. 1-368 p.</ref>. All information related to blockchain transactions is at once both independently verifiable by all (even outside) parties as correct and also inscrutable to entities without explicit permission. The first and probably most well-known implementation of blockchain technology is [https://bitcoin.org Bitcoin] <ref name="BTC">Nakamoto S. Bitcoin: A Peer-to-Peer Electronic Cash System. WwwBitcoinOrg [Internet]. 2008;9. Available from: https://bitcoin.org/bitcoin.pdf</ref>, but there has been a massive expansion of blockchain use-cases since Bitcoin's initial introduction.<br />
<br />
<br />
<br />
== What is the Blockchain? ==<br />
<br />
First, it should be clear that there is no one blockchain to rule them all. "The Blockchain," as it is often referred, really is a concept of a series (chain) of interrelated sets (blocks) of encrypted information. Hence a chain of blocks, or blockchain. There are many such blockchains in existence, and one could choose to do transactions on any one of them or create a new blockchain.<br />
<br />
<br />
An important aspect of most blockchains is that they are designed to be maintained on a distributed network of multiple nodes. Each node holds a complete copy of the blockchain and adds each sequential new block as it is created. This system allows every transaction on the blockchain to be verified by any or all of the nodes in the network, and also makes it very difficult for the information held in the blockchain to become lost or unavailable if any one or even most of the nodes go offline.<br />
<br />
<br />
Transactions that are set to be added to the blockchain are added to the newest block as soon as it is created. This makes the continued existence of the blockchain dependent on the creation of new blocks. There are several main methods for the creation of new blocks on the network, and the choice of method depends somewhat on the purpose of the blockchain in question. Bitcoin, the first cryptocurrency, uses a method called Proof of Work, but there are at least two methods currently in use:<br />
* [https://en.wikipedia.org/wiki/Proof-of-work_system Proof of Work System (Wikipedia)]<br />
** In the traditional Proof of Work System, each block validator, or "miner," competes to validate the block by processing a task. The winner is the first person to complete this task. The chance of completion of the task is random based on a hash function, but increases with the more "work" a person puts into the task. The system can automatically vary the difficulty of the task to limit the speed of block generation. The winner is credited for his/her work by a small amount of currency. <br />
* [https://en.wikipedia.org/wiki/Proof-of-stake Proof of Stake (Wikipedia)] [https://en.bitcoin.it/wiki/Proof_of_Stake Proof of Stake (Bitcoin Wiki)]<br />
** There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake<ref>Siim, Janno. "Proof-of-Stake."</ref>. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker.<br />
<br />
<br />
The blockchain has moved beyond simply processing transactions of cryptocurrency such as Bitcoin. Any data that can be encoded into a cryptographic [https://en.wikipedia.org/wiki/Hash_function hash] can be added to a blockchain. Various different ideas have been proposed, and I will not attempt to list them here, but they are wide ranging. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0<ref>Swan, M. (2015). Blockchain: Blueprint for a new economy: " O'Reilly Media, Inc."</ref>. Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education.<br />
<br />
<br />
=== Blockchain Development Groups ===<br />
Certainly a non-exhaustive list . . .<br />
<br />
* [https://bitcoin.org/en/ Bitcoin]<br />
<br />
* [https://hyperledger.org The Hyperledger Project]<br />
<br />
* [https://ethereum.org The Ethereum Project]<br />
<br />
* [https://r3cev.com/blog/2016/4/4/introducing-r3-corda-a-distributed-ledger-designed-for-financial-services The CORDA Platform]<br />
<br />
* [http://www.muskokagroup.org/ The Muskoka Group]<br />
<br />
* [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab The ONC Tech Lab]<br />
<br />
== Blockchain Use Cases ==<br />
<br />
=== Cryptocurrency ===<br />
Bitcoin (BTC) was the first cryptocurrency based on the blockchain and was developed by someone calling himself (or herself) Satoshi Nakamoto. The protocol was introduced in 2008 after the publication of a white paper<ref name="BTC" /> describing the algorithm and the mechanisms for generation and distribution of BTC. At this point there are hundreds of cryptocurrencies in circulation according to [http://wikipedia.org Wikipedia], many of which are based on the Bitcoin blockchain, but only a few have gone into widespread use<ref>https://en.wikipedia.org/wiki/List_of_cryptocurrencies</ref>.<br />
<br />
=== Smart Contracts ===<br />
One of the major potential functions of blockchain technology is through the creation of smart contracts. Various components of contracts, including proof of the involved parties, requirements for completion, and actions upon completion of the contract can be encoded in blocks. These can then be added to a blockchain and become available for independent verification, which can even lead to automatic processing of contracts when their requirements have been fulfilled.<br />
<br />
Smart contracts are scripts which have various rules and logic that automatically execute when those rules are met. Smart contracts allow heavily automated workflows between transacting parties in the network while maintaining anonymity. Once the contract has been executed, one can take custody over assets or pre-defined payments can be issued. <ref>Christidis, K & Devetsikiotis, M. (2016, May 10). Blockchains and Smart Contracts for the Internet of Things. IEEE Access, 4, 2292-2303. doi: 10.1109/ACCESS.2016.2566339</ref> They are importantly different in the sense that they are stored on a distributed network and they can be verified as true without knowledge of the contract specifications <ref>https://bitsonblocks.net/2016/02/01/a-gentle-introduction-to-smart-contracts/</ref>.<br />
<br />
[https://ethereum.org The Ethereum Project] was one of the first to introduce the concept of smart contracts using their alternative blockchain and currency token, [https://www.ethereum.org/ether ether].<br />
<br />
=== Securities Exchanges and Finance ===<br />
<br />
One of the hottest arenas for blockchain development currently is in the financial markets, an extension of the original cryptocurrency use cases for the blockchain. Multiple stock markets and other financial firms have initiated investigations and pilot projects into the feasibility and utility of the blockchain for contracts and tracking of financial instruments. NASDAQ has been one of the first major markets to put blockchain technology into use, and has released some information on its implementation, called Linq <ref>http://ir.nasdaq.com/releasedetail.cfm?releaseid=948326</ref><ref>http://www.coindesk.com/hands-on-with-linq-nasdaqs-private-markets-blockchain-project/</ref>. The cryptocurrency website [http://www.coindesk.com Coindesk] has also produced a list of 10 exchanges using or investigating blockchain technologies<ref>http://www.coindesk.com/10-stock-exchanges-blockchain/</ref>.<br />
<br />
<br />
Additionally, financial firms such as Visa have been experimenting with the blockchain for keeping track of transactions as well as with proof of concept applications such as remittance<ref>http://www.coindesk.com/hands-on-with-visa-europes-bitcoin-remittance-app/</ref>.<br />
<br />
== Advantages and Disadvantages of Blockchain ==<br />
<br />
Blockchain is a novel concept and is being explored in various sectors. While there may be several applications and limitations of this technology in future, some of them are highlighted below<ref>Fauvel, W. (2017, August 11). Blockchain Advantage and Disadvantages. Medium. Retrieved from: https://medium.com/nudjed/blockchain-advantage-and-disadvantages-e76dfde3bbc0</ref>:<br />
<br />
=== Pros: ===<br />
# Distributed: There is no single owner of the database. As anyone can contribute and be a part of the network, the risks of data tampering and fraud are minimal. As Nakamoto <ref name="BTC" /> mentioned, as long as the majority of nodes are honest, a random attacker would not be able to alter the history.<br />
# Trustless: As every node in the network will have a copy of the blockchain and they verify the transactions independently. Hence, this system allows transaction even if the parties don't trust each other.<br />
# Immutable: Once the transaction is verified and embedded in the blockchain, it is almost impossible to undo it, and the complexity increases with time as more blocks are added downstream. This allows keeping a track of accurate events that occurred through the history.<br />
# Decentralized: There is no middleman like banks or data owners. This helps avoid manipulation of the market by the owners.<br />
<br />
<br />
=== Cons: ===<br />
# Waste of resources: As several nodes are running and utilizing a huge amount of computing power and electricity to verify and maintain the blockchain, there is more than required redundancy. <br />
# Higher cost for less value: With time, the use of network increases and the complexity of the hashing algorithm also increases. Hence, more resources are required for the same amount of work. This increases the cost of work and transactions gets slower, as miners prioritize the transactions with higher incentives causing a backlog the transactions with smaller values. <br />
# Difficulty to keep up with the size of the block: As the size continues to grow along with the complexity to solve the calculation, new nodes with smaller computing power will have difficulty joining the network and likewise, the older and slower nodes will gradually fade with decreasing incentive for the work. Hence, like Darwin’s theory of the "survival of the fittest", a few larger nodes will dominate the network creating more and more centralization of the system. <br />
# Speculative market: Due to the lack of proper regulation of this system, the market is subject to a great volatility and thus making it risky for investors. <br />
# Immutable smart contracts: As there are clear advantages of having permanent and immutable records, at the same time, there is a bitter flipside to this. For example, if there is a flaw with code that can compromise the system, it is also irreparable and creates the opportunity for the attackers to exploit the same flaw repetitively in future. As time progresses, the capability of repairing the error will be even more complex.<br />
<br />
<br />
<br />
== Potential Use Cases in Healthcare ==<br />
Though there has yet to be a breakthrough report or use-case for blockchain technology in healthcare, there are many potential ways that the blockchain could be implemented within the current healthcare structure. Any list will likely be incomplete, but these examples represent some of the published and available literature on blockchain implementations in health.<br />
<br />
=== Health Information Exchange (HIE) ===<br />
One major area that blockchains may be able to facilitate is the secure access to and communication of patient health records between individuals and institutions. There have been multiple white papers published on the topic, including groups from the Mayo Clinic <ref>Peterson K, Deeduvanu R, Kanjamala P, Boles K. A Blockchain-Based Approach to Health Information Exchange Networks. (1):1–10.</ref> and MIT <ref>Ekblaw A, Azaria A, Halamka JD, Lippman A, Original I, Vieira T. A Case Study for Blockchain in Healthcare: “ MedRec ” prototype for electronic health records and medical research data MedRec: Using Blockchain for Medical Data Access and Permission Management [Internet]. 2016. Available from: https://www.healthit.gov/sites/default/files/5-56-onc_blockchainchallenge_mitwhitepaper.pdf</ref> who described a system for patient information exchange based on blockchain technology that would allow patient-controlled access to records across institutions using HL7 Fast Healthcare Interoperability Resources ([[FHIR]]), [http://json.org JSON], or other encoding system. In these models the actual health care data are not encoded in the blockchain, but are merely references pointing to where the data reside, such as at institutions or in a "data lake" <ref>Linn LA, Koo MB. Blockchain For Health Data and Its Potential Use in Health IT and Health Care Related Research. 2014;1–10.</ref>. Similarly, a group out of China described an app called Healthcare Data Gateway (HGD) that allows patients to view and directly control rule-based access to their health records with a smart phone interface and authentication provided by a blockchain network <ref>Yue X, Wang H, Jin D, Li M, Jiang W. Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst [Internet]. 2016 Oct;40(10):218. Available from: http://dx.doi.org/10.1007/s10916-016-0574-6</ref>. These ideas support the concept of patient-owned medical data, and would have the effect of decentralization of medical records in ways that are as yet undetermined.<br />
<br />
=== Health Research Integrity ===<br />
Academic research is a major driver of advances in health care, but in the setting of limited funding and publication pressures on researchers significant concerns have been raised regarding research integrity<ref>Titus SL, Wells J a, Rhoades LJ. Repairing research integrity. Nature [Internet]. 2008 Jun 19;453(7198):980–2. Available from: http://www.ncbi.nlm.nih.gov/pubmed/18563131</ref>. Organizations such as [http://clinicaltrials.gov ClinicalTrials.gov] and others have been developed to help drive researchers to define endpoints and analysis prior to conducting clinical trials and other studies. As it represents an immutable, verifiable record of events and transactions, the blockchain has been proposed as a potential decentralized resources for helping to ensure biomedical research integrity. Benjamin Carlisle<ref>Carlisle BG. Proof of prespecified endpoints in medical research with the bitcoin blockchain [Internet]. 2014. Available from: http://www.bgcarlisle.com/blog/2014/08/25/proof-of-prespecified-endpoints-in-medical-research-with-the-bitcoin-blockchain/</ref>, followed by several researchers from the UK<ref>Irving G, Holden J. How blockchain-timestamped protocols could improve the trustworthiness of medical science. F1000Research [Internet]. 2016;5:222. Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4866630/</ref>, proposed in 2014 that researchers could use the blockchain to record pre-specified aspects of their projects, including the study design, analysis plan, and data structure, among others, which could later be verified by consumers of the literature to decrease bias that may be introduced in post-hoc analysis<ref>Slade E, Drysdale H, Goldacre B, COMPare Team. Discrepancies Between Prespecified and Reported Outcomes. Ann Intern Med [Internet]. 2016 Mar 1;164(5):374. Available from: http://www.ncbi.nlm.nih.gov/pubmed/26720309</ref>. The blockchain also offers the potential ability to verify the integrity of actual research data and analysis by outside observers, even if the data themselves are not made publicly available. These types of implementations may lead to improvements in both the integrity of biomedical research as well as bolster public trust in medical research.<br />
<br />
=== Personal Health Records ===<br />
This concept dovetails with the idea of HIE using the blockchain, but focuses more on the secure maintenance of a personal health record (PHR) by patients. No production PHR has been released based on this technology, but concepts such as MedVault <ref>Baxendale G. Can Blockchain Revolutionise EPRs? [Internet]. Vol. 58, ITNOW. 2016. p. 38–9. Available from: http://itnow.oxfordjournals.org/lookup/doi/10.1093/itnow/bww017</ref> use alternative blockchains such as [http://www.Colu.com Colu] to store patient data directly on the blockchain. Others such as [https://devpost.com/software/ehealthwallet eHealthWallet] have also developed prototype PHRs based on the blockchain. Patients could then share or authorize doctors and other health entities to access and modify their data.<br />
<br />
The majority of the proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference<ref>Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230</ref><ref>Yue, X., Wang, H., Jin, D., Li, M., & Jiang, W. (2016). Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst, 40(10), 218. doi:10.1007/s10916-016-0574-6</ref>. <br />
* In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care.<br />
* As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed.<br />
* A blockchain-enabled smart contracts controlled by the patient can be used to authorize direct sharing of medical record between institutions. Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability<ref>Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230</ref>: <br />
* Digital access rules: The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application<br />
* Data aggregation: Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health<br />
* Data liquidity: Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc.<br />
* Patient identity: Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems<br />
* Data immutability: Since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time.<br />
<br />
=== Storage of Health Care Data ===<br />
Most of the previous examples use the blockchain not as a direct data storage medium, but instead as a secure reference point for identities, access, and data locations. At least one group from a company called Tierion, which partners with the [http://www.2.forms.healthcare.philips.com/blockchainlabs Philips Blockchain Lab ], has produced a concept called Chainpoint<ref>Vaughan AW, Bukowski J, Wilkinson S, Sporny CM, Shea R, Allen C, et al. Chainpoint: A scalable protocol for anchoring data in the blockchain and generating blockchain receipts [Internet]. 2016. Available from: https://tierion.com/chainpoint</ref>, which proposes to use a [https://proofofexistence.com/about Proof of Existence] concept and Merkle Roots<ref>Merkle RC. PROTOCOLS FOR PUBUC KEY CRYPTOSYSTEMS. In: IEEE Symposium on Security and Privacy [Internet]. 1980. p. 122–34. Available from: http://www.merkle.com/papers/Protocols.pdf</ref> to efficiently store actual patient records on the blockchain without imposing excessive transaction demands on the system.<br />
<br />
=== Billing and Claims Adjudication ===<br />
Blockchain system can help reduce administrative costs and time while automating claims adjudication and payment processing using smart contracts. For example - a smart contract is set up between payer or insurance company, provider, and patient such that when the patient sees a provider, or if a procedure is done, an entry is recorded in the blockchain. Based on the criteria set, the contract can automatically issue reimbursement from the payer as well as co-pay from the patient without having to wait for the insurance approval.<ref>Srinivasan, P. (2017, November 9). Healthcare Blockchain: How Smart Contracts Could Revolutionize Care Delivery. Prolifics. Retrieved from: https://www.prolifics.com/blog/healthcare-blockchain-how-smart-contracts-could-revolutionize-care-delivery</ref><br />
<br />
=== Drug Supply Chain and Prescription Management ===<br />
Counterfeit drugs are a major problem especially in the developing country where it is estimated that about 1 in 10 medical products are counterfeit <ref>WHO. (2017, November 28). 1 in 10 medical products in developing countries is substandard or falsified. Retrieved from: http://www.who.int/en/news-room/detail/28-11-2017-1-in-10-medical-products-in-developing-countries-is-substandard-or-falsified</ref>. Ensuring the integrity of the drug and maintaining a robust audit trail is a must to ensure patient safety. Similarly, this platform can be used in prescription drug management and track history and authenticate prescriptions using smart-contracts. <br />
<br />
=== Few Examples of Current Use Cases and Future Development ===<br />
<br />
* MedRec- it is based on Ethereum platform and focuses on medical data management using smart contracts like managing permissions and authentication processes, data sharing in an interoperable environment between healthcare systems and maintaining an audit log. <ref>Azaria, A., Ekblaw, A., Vieira, T., & Lippman, A. (2016, August 22-24). MedRec: Using Blockchain for Medical Data Access and Permission Management. 2016 2nd International Conference on Open and Big Data (OBD). doi:10.1109/obd.2016.11</ref><br />
<br />
* Guardtime- also focuses on medical data management and has partnered with e-Health authority of Estonia to secure the country's database of health records <ref>Ruubel M. (2016, February 12). Estonian eHealth Authority Partners with Guardtime to Accelerate Transparency and Auditability in Health Care. Retrieved from: https://guardtime.com/blog/estonian-ehealth-partners-guardtime-blockchain-based-transparency</ref>. Also, recently, MyPCR smartphone platform from Guardtime has partnered with Instant Access Medical and Healthcare Gateway in the UK for patient health data management and verification of medication adherence. <ref>Ruubel M. (2018, June 20). World’s first blockchain-supported Personal Care Record Platform launched by Guardtime and partners to up to 30 million NHS patients in the UK. Retrieved from: https://guardtime.com/blog/world-s-first-blockchain-supported-personal-care-record-platform-launched-by-guardtime-and-partners</ref> <br />
<br />
* Blockchain Health- created for healthcare research data management where users can individually authorize the release of their health information to researchers as well as track the use of their data. <ref>BlockchainHealth. (2016). Blockchain for health research. Retrieved from: https://blockchainhealth.co/</ref><br />
<br />
* BlockMedx- it is a startup company which intends to use the blockchain platform to transmit DEA controlled drug prescriptions from physicians to pharmacies and then to patients securely. <ref>BlockMedx. (2018). Retrieved from: https://blockmedx.com/en/</ref><br />
<br />
* MediLedger- another pharmaceutical supply chain management startup company who has partnered with several drug manufacturers and aims to provide an open, secure and interoperable network. <ref>MediLedger. (2018). The MediLedger Project. Retrieved from: https://mediledger.com/</ref><br />
<br />
* Drug and Pharmacy Verification - [https://devpost.com/software/veripharm VeriPharm] has developed a proof of concept that would help track and verify pharmaceuticals from the raw materials to the final product administered to patients.<br />
<br />
* Appointment Scheduling on the Blockchain - [https://devpost.com/software/dhva-appointment-blocks dhva-apointment-blocks]<br />
<br />
* Care Coordination - Projects such as [https://devpost.com/software/simplyvitahlth simplyvitahlth] are geared toward coordinating care between multiple providers and at different institutions to ensure that complex care pathways are being followed appropriately.<br />
<br />
<br />
There are many more potential use-cases for blockchain technology within healthcare, and undoubtedly we will continue to see development in this area in coming years. In 2016, a consortium of sponsors led by [https://gem.co/ Gem] (Whitepaper)<ref>Wood C, Winton B, Carter K, Benkert S, Dodd L, Bradley J, et al. How Blockchain Technology Can Enhance Ehr Operability [Internet]. 2016. Available from: http://research.ark-invest.com/blockchain-and-healthcare</ref> held the first healthcare oriented blockchain conference, [https://godistributed.com/health Distributed: Health] in Nashville, TN. Similarly, the Office of the National Coordinator (ONC) Tech Lab had issued a Blockchain Challenge in July, 2016.<ref>https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab</ref><br />
* The list of submissions and awards can be found [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab here]<br />
<br />
As the healthcare blockchain community grows, gatherings such as these will likely increase and blockchain technologies will increasingly be introduced at major medical conferences.<br />
<br />
== References ==<br />
<references /><br />
<br />
Submitted by Sandeep Regmi<br />
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[[Category: Other Technologies]]</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/The_Blockchain_in_HealthcareThe Blockchain in Healthcare2018-10-19T02:54:23Z<p>Phamnh: /* Personal Health Records */</p>
<hr />
<div>The blockchain is an idea centered around the concept of a secure, digital ledger system that provides a system for efficient, auditable transactions of almost any type between entities <ref>Tapscott D, Tapscott A. Blockchain Revolution: How the Technology Behind Bitcoin Is Changing Money, Business, and the World. United States: Portfolio; 2016. 1-368 p.</ref>. All information related to blockchain transactions is at once both independently verifiable by all (even outside) parties as correct and also inscrutable to entities without explicit permission. The first and probably most well-known implementation of blockchain technology is [https://bitcoin.org Bitcoin] <ref name="BTC">Nakamoto S. Bitcoin: A Peer-to-Peer Electronic Cash System. WwwBitcoinOrg [Internet]. 2008;9. Available from: https://bitcoin.org/bitcoin.pdf</ref>, but there has been a massive expansion of blockchain use-cases since Bitcoin's initial introduction.<br />
<br />
<br />
<br />
== What is the Blockchain? ==<br />
<br />
First, it should be clear that there is no one blockchain to rule them all. "The Blockchain," as it is often referred, really is a concept of a series (chain) of interrelated sets (blocks) of encrypted information. Hence a chain of blocks, or blockchain. There are many such blockchains in existence, and one could choose to do transactions on any one of them or create a new blockchain.<br />
<br />
<br />
An important aspect of most blockchains is that they are designed to be maintained on a distributed network of multiple nodes. Each node holds a complete copy of the blockchain and adds each sequential new block as it is created. This system allows every transaction on the blockchain to be verified by any or all of the nodes in the network, and also makes it very difficult for the information held in the blockchain to become lost or unavailable if any one or even most of the nodes go offline.<br />
<br />
<br />
Transactions that are set to be added to the blockchain are added to the newest block as soon as it is created. This makes the continued existence of the blockchain dependent on the creation of new blocks. There are several main methods for the creation of new blocks on the network, and the choice of method depends somewhat on the purpose of the blockchain in question. Bitcoin, the first cryptocurrency, uses a method called Proof of Work, but there are at least two methods currently in use:<br />
* [https://en.wikipedia.org/wiki/Proof-of-work_system Proof of Work System (Wikipedia)]<br />
** In the traditional Proof of Work System, each block validator, or "miner," competes to validate the block by processing a task. The winner is the first person to complete this task. The chance of completion of the task is random based on a hash function, but increases with the more "work" a person puts into the task. The system can automatically vary the difficulty of the task to limit the speed of block generation. The winner is credited for his/her work by a small amount of currency. <br />
* [https://en.wikipedia.org/wiki/Proof-of-stake Proof of Stake (Wikipedia)] [https://en.bitcoin.it/wiki/Proof_of_Stake Proof of Stake (Bitcoin Wiki)]<br />
** There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake<ref>Siim, Janno. "Proof-of-Stake."</ref>. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker.<br />
<br />
<br />
The blockchain has moved beyond simply processing transactions of cryptocurrency such as Bitcoin. Any data that can be encoded into a cryptographic [https://en.wikipedia.org/wiki/Hash_function hash] can be added to a blockchain. Various different ideas have been proposed, and I will not attempt to list them here, but they are wide ranging. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0<ref>Swan, M. (2015). Blockchain: Blueprint for a new economy: " O'Reilly Media, Inc."</ref>. Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education.<br />
<br />
<br />
=== Blockchain Development Groups ===<br />
Certainly a non-exhaustive list . . .<br />
<br />
* [https://bitcoin.org/en/ Bitcoin]<br />
<br />
* [https://hyperledger.org The Hyperledger Project]<br />
<br />
* [https://ethereum.org The Ethereum Project]<br />
<br />
* [https://r3cev.com/blog/2016/4/4/introducing-r3-corda-a-distributed-ledger-designed-for-financial-services The CORDA Platform]<br />
<br />
* [http://www.muskokagroup.org/ The Muskoka Group]<br />
<br />
* [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab The ONC Tech Lab]<br />
<br />
== Blockchain Use Cases ==<br />
<br />
=== Cryptocurrency ===<br />
Bitcoin (BTC) was the first cryptocurrency based on the blockchain and was developed by someone calling himself (or herself) Satoshi Nakamoto. The protocol was introduced in 2008 after the publication of a white paper<ref name="BTC" /> describing the algorithm and the mechanisms for generation and distribution of BTC. At this point there are hundreds of cryptocurrencies in circulation according to [http://wikipedia.org Wikipedia], many of which are based on the Bitcoin blockchain, but only a few have gone into widespread use<ref>https://en.wikipedia.org/wiki/List_of_cryptocurrencies</ref>.<br />
<br />
=== Smart Contracts ===<br />
One of the major potential functions of blockchain technology is through the creation of smart contracts. Various components of contracts, including proof of the involved parties, requirements for completion, and actions upon completion of the contract can be encoded in blocks. These can then be added to a blockchain and become available for independent verification, which can even lead to automatic processing of contracts when their requirements have been fulfilled.<br />
<br />
Smart contracts are scripts which have various rules and logic that automatically execute when those rules are met. Smart contracts allow heavily automated workflows between transacting parties in the network while maintaining anonymity. Once the contract has been executed, one can take custody over assets or pre-defined payments can be issued. <ref>Christidis, K & Devetsikiotis, M. (2016, May 10). Blockchains and Smart Contracts for the Internet of Things. IEEE Access, 4, 2292-2303. doi: 10.1109/ACCESS.2016.2566339</ref> They are importantly different in the sense that they are stored on a distributed network and they can be verified as true without knowledge of the contract specifications <ref>https://bitsonblocks.net/2016/02/01/a-gentle-introduction-to-smart-contracts/</ref>.<br />
<br />
[https://ethereum.org The Ethereum Project] was one of the first to introduce the concept of smart contracts using their alternative blockchain and currency token, [https://www.ethereum.org/ether ether].<br />
<br />
=== Securities Exchanges and Finance ===<br />
<br />
One of the hottest arenas for blockchain development currently is in the financial markets, an extension of the original cryptocurrency use cases for the blockchain. Multiple stock markets and other financial firms have initiated investigations and pilot projects into the feasibility and utility of the blockchain for contracts and tracking of financial instruments. NASDAQ has been one of the first major markets to put blockchain technology into use, and has released some information on its implementation, called Linq <ref>http://ir.nasdaq.com/releasedetail.cfm?releaseid=948326</ref><ref>http://www.coindesk.com/hands-on-with-linq-nasdaqs-private-markets-blockchain-project/</ref>. The cryptocurrency website [http://www.coindesk.com Coindesk] has also produced a list of 10 exchanges using or investigating blockchain technologies<ref>http://www.coindesk.com/10-stock-exchanges-blockchain/</ref>.<br />
<br />
<br />
Additionally, financial firms such as Visa have been experimenting with the blockchain for keeping track of transactions as well as with proof of concept applications such as remittance<ref>http://www.coindesk.com/hands-on-with-visa-europes-bitcoin-remittance-app/</ref>.<br />
<br />
== Advantages and Disadvantages of Blockchain ==<br />
<br />
Blockchain is a novel concept and is being explored in various sectors. While there may be several applications and limitations of this technology in future, some of them are highlighted below<ref>Fauvel, W. (2017, August 11). Blockchain Advantage and Disadvantages. Medium. Retrieved from: https://medium.com/nudjed/blockchain-advantage-and-disadvantages-e76dfde3bbc0</ref>:<br />
<br />
=== Pros: ===<br />
# Distributed: There is no single owner of the database. As anyone can contribute and be a part of the network, the risks of data tampering and fraud are minimal. As Nakamoto <ref name="BTC" /> mentioned, as long as the majority of nodes are honest, a random attacker would not be able to alter the history.<br />
# Trustless: As every node in the network will have a copy of the blockchain and they verify the transactions independently. Hence, this system allows transaction even if the parties don't trust each other.<br />
# Immutable: Once the transaction is verified and embedded in the blockchain, it is almost impossible to undo it, and the complexity increases with time as more blocks are added downstream. This allows keeping a track of accurate events that occurred through the history.<br />
# Decentralized: There is no middleman like banks or data owners. This helps avoid manipulation of the market by the owners.<br />
<br />
<br />
=== Cons: ===<br />
# Waste of resources: As several nodes are running and utilizing a huge amount of computing power and electricity to verify and maintain the blockchain, there is more than required redundancy. <br />
# Higher cost for less value: With time, the use of network increases and the complexity of the hashing algorithm also increases. Hence, more resources are required for the same amount of work. This increases the cost of work and transactions gets slower, as miners prioritize the transactions with higher incentives causing a backlog the transactions with smaller values. <br />
# Difficulty to keep up with the size of the block: As the size continues to grow along with the complexity to solve the calculation, new nodes with smaller computing power will have difficulty joining the network and likewise, the older and slower nodes will gradually fade with decreasing incentive for the work. Hence, like Darwin’s theory of the "survival of the fittest", a few larger nodes will dominate the network creating more and more centralization of the system. <br />
# Speculative market: Due to the lack of proper regulation of this system, the market is subject to a great volatility and thus making it risky for investors. <br />
# Immutable smart contracts: As there are clear advantages of having permanent and immutable records, at the same time, there is a bitter flipside to this. For example, if there is a flaw with code that can compromise the system, it is also irreparable and creates the opportunity for the attackers to exploit the same flaw repetitively in future. As time progresses, the capability of repairing the error will be even more complex.<br />
<br />
<br />
<br />
== Potential Use Cases in Healthcare ==<br />
Though there has yet to be a breakthrough report or use-case for blockchain technology in healthcare, there are many potential ways that the blockchain could be implemented within the current healthcare structure. Any list will likely be incomplete, but these examples represent some of the published and available literature on blockchain implementations in health.<br />
<br />
=== Health Information Exchange (HIE) ===<br />
One major area that blockchains may be able to facilitate is the secure access to and communication of patient health records between individuals and institutions. There have been multiple white papers published on the topic, including groups from the Mayo Clinic <ref>Peterson K, Deeduvanu R, Kanjamala P, Boles K. A Blockchain-Based Approach to Health Information Exchange Networks. (1):1–10.</ref> and MIT <ref>Ekblaw A, Azaria A, Halamka JD, Lippman A, Original I, Vieira T. A Case Study for Blockchain in Healthcare: “ MedRec ” prototype for electronic health records and medical research data MedRec: Using Blockchain for Medical Data Access and Permission Management [Internet]. 2016. Available from: https://www.healthit.gov/sites/default/files/5-56-onc_blockchainchallenge_mitwhitepaper.pdf</ref> who described a system for patient information exchange based on blockchain technology that would allow patient-controlled access to records across institutions using HL7 Fast Healthcare Interoperability Resources ([[FHIR]]), [http://json.org JSON], or other encoding system. In these models the actual health care data are not encoded in the blockchain, but are merely references pointing to where the data reside, such as at institutions or in a "data lake" <ref>Linn LA, Koo MB. Blockchain For Health Data and Its Potential Use in Health IT and Health Care Related Research. 2014;1–10.</ref>. Similarly, a group out of China described an app called Healthcare Data Gateway (HGD) that allows patients to view and directly control rule-based access to their health records with a smart phone interface and authentication provided by a blockchain network <ref>Yue X, Wang H, Jin D, Li M, Jiang W. Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst [Internet]. 2016 Oct;40(10):218. Available from: http://dx.doi.org/10.1007/s10916-016-0574-6</ref>. These ideas support the concept of patient-owned medical data, and would have the effect of decentralization of medical records in ways that are as yet undetermined.<br />
<br />
=== Health Research Integrity ===<br />
Academic research is a major driver of advances in health care, but in the setting of limited funding and publication pressures on researchers significant concerns have been raised regarding research integrity<ref>Titus SL, Wells J a, Rhoades LJ. Repairing research integrity. Nature [Internet]. 2008 Jun 19;453(7198):980–2. Available from: http://www.ncbi.nlm.nih.gov/pubmed/18563131</ref>. Organizations such as [http://clinicaltrials.gov ClinicalTrials.gov] and others have been developed to help drive researchers to define endpoints and analysis prior to conducting clinical trials and other studies. As it represents an immutable, verifiable record of events and transactions, the blockchain has been proposed as a potential decentralized resources for helping to ensure biomedical research integrity. Benjamin Carlisle<ref>Carlisle BG. Proof of prespecified endpoints in medical research with the bitcoin blockchain [Internet]. 2014. Available from: http://www.bgcarlisle.com/blog/2014/08/25/proof-of-prespecified-endpoints-in-medical-research-with-the-bitcoin-blockchain/</ref>, followed by several researchers from the UK<ref>Irving G, Holden J. How blockchain-timestamped protocols could improve the trustworthiness of medical science. F1000Research [Internet]. 2016;5:222. Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4866630/</ref>, proposed in 2014 that researchers could use the blockchain to record pre-specified aspects of their projects, including the study design, analysis plan, and data structure, among others, which could later be verified by consumers of the literature to decrease bias that may be introduced in post-hoc analysis<ref>Slade E, Drysdale H, Goldacre B, COMPare Team. Discrepancies Between Prespecified and Reported Outcomes. Ann Intern Med [Internet]. 2016 Mar 1;164(5):374. Available from: http://www.ncbi.nlm.nih.gov/pubmed/26720309</ref>. The blockchain also offers the potential ability to verify the integrity of actual research data and analysis by outside observers, even if the data themselves are not made publicly available. These types of implementations may lead to improvements in both the integrity of biomedical research as well as bolster public trust in medical research.<br />
<br />
=== Personal Health Records ===<br />
This concept dovetails with the idea of HIE using the blockchain, but focuses more on the secure maintenance of a personal health record (PHR) by patients. No production PHR has been released based on this technology, but concepts such as MedVault <ref>Baxendale G. Can Blockchain Revolutionise EPRs? [Internet]. Vol. 58, ITNOW. 2016. p. 38–9. Available from: http://itnow.oxfordjournals.org/lookup/doi/10.1093/itnow/bww017</ref> use alternative blockchains such as [http://www.Colu.com Colu] to store patient data directly on the blockchain. Others such as [https://devpost.com/software/ehealthwallet eHealthWallet] have also developed prototype PHRs based on the blockchain. Patients could then share or authorize doctors and other health entities to access and modify their data.<br />
<br />
The majority of the proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference<ref>Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230</ref><ref>Yue, X., Wang, H., Jin, D., Li, M., & Jiang, W. (2016). Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst, 40(10), 218. doi:10.1007/s10916-016-0574-6</ref>. <br />
* In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care.<br />
* As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed.<br />
* A blockchain-enabled smart contracts controlled by the patient can be used to authorize direct sharing of medical record between institutions. Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability[6]: <br />
* Digital access rules: The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application<br />
* Data aggregation: Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health<br />
* Data liquidity: Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc.<br />
* Patient identity: Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems<br />
* Data immutability: Since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time.<br />
<br />
=== Storage of Health Care Data ===<br />
Most of the previous examples use the blockchain not as a direct data storage medium, but instead as a secure reference point for identities, access, and data locations. At least one group from a company called Tierion, which partners with the [http://www.2.forms.healthcare.philips.com/blockchainlabs Philips Blockchain Lab ], has produced a concept called Chainpoint<ref>Vaughan AW, Bukowski J, Wilkinson S, Sporny CM, Shea R, Allen C, et al. Chainpoint: A scalable protocol for anchoring data in the blockchain and generating blockchain receipts [Internet]. 2016. Available from: https://tierion.com/chainpoint</ref>, which proposes to use a [https://proofofexistence.com/about Proof of Existence] concept and Merkle Roots<ref>Merkle RC. PROTOCOLS FOR PUBUC KEY CRYPTOSYSTEMS. In: IEEE Symposium on Security and Privacy [Internet]. 1980. p. 122–34. Available from: http://www.merkle.com/papers/Protocols.pdf</ref> to efficiently store actual patient records on the blockchain without imposing excessive transaction demands on the system.<br />
<br />
=== Billing and Claims Adjudication ===<br />
Blockchain system can help reduce administrative costs and time while automating claims adjudication and payment processing using smart contracts. For example - a smart contract is set up between payer or insurance company, provider, and patient such that when the patient sees a provider, or if a procedure is done, an entry is recorded in the blockchain. Based on the criteria set, the contract can automatically issue reimbursement from the payer as well as co-pay from the patient without having to wait for the insurance approval.<ref>Srinivasan, P. (2017, November 9). Healthcare Blockchain: How Smart Contracts Could Revolutionize Care Delivery. Prolifics. Retrieved from: https://www.prolifics.com/blog/healthcare-blockchain-how-smart-contracts-could-revolutionize-care-delivery</ref><br />
<br />
=== Drug Supply Chain and Prescription Management ===<br />
Counterfeit drugs are a major problem especially in the developing country where it is estimated that about 1 in 10 medical products are counterfeit <ref>WHO. (2017, November 28). 1 in 10 medical products in developing countries is substandard or falsified. Retrieved from: http://www.who.int/en/news-room/detail/28-11-2017-1-in-10-medical-products-in-developing-countries-is-substandard-or-falsified</ref>. Ensuring the integrity of the drug and maintaining a robust audit trail is a must to ensure patient safety. Similarly, this platform can be used in prescription drug management and track history and authenticate prescriptions using smart-contracts. <br />
<br />
=== Few Examples of Current Use Cases and Future Development ===<br />
<br />
* MedRec- it is based on Ethereum platform and focuses on medical data management using smart contracts like managing permissions and authentication processes, data sharing in an interoperable environment between healthcare systems and maintaining an audit log. <ref>Azaria, A., Ekblaw, A., Vieira, T., & Lippman, A. (2016, August 22-24). MedRec: Using Blockchain for Medical Data Access and Permission Management. 2016 2nd International Conference on Open and Big Data (OBD). doi:10.1109/obd.2016.11</ref><br />
<br />
* Guardtime- also focuses on medical data management and has partnered with e-Health authority of Estonia to secure the country's database of health records <ref>Ruubel M. (2016, February 12). Estonian eHealth Authority Partners with Guardtime to Accelerate Transparency and Auditability in Health Care. Retrieved from: https://guardtime.com/blog/estonian-ehealth-partners-guardtime-blockchain-based-transparency</ref>. Also, recently, MyPCR smartphone platform from Guardtime has partnered with Instant Access Medical and Healthcare Gateway in the UK for patient health data management and verification of medication adherence. <ref>Ruubel M. (2018, June 20). World’s first blockchain-supported Personal Care Record Platform launched by Guardtime and partners to up to 30 million NHS patients in the UK. Retrieved from: https://guardtime.com/blog/world-s-first-blockchain-supported-personal-care-record-platform-launched-by-guardtime-and-partners</ref> <br />
<br />
* Blockchain Health- created for healthcare research data management where users can individually authorize the release of their health information to researchers as well as track the use of their data. <ref>BlockchainHealth. (2016). Blockchain for health research. Retrieved from: https://blockchainhealth.co/</ref><br />
<br />
* BlockMedx- it is a startup company which intends to use the blockchain platform to transmit DEA controlled drug prescriptions from physicians to pharmacies and then to patients securely. <ref>BlockMedx. (2018). Retrieved from: https://blockmedx.com/en/</ref><br />
<br />
* MediLedger- another pharmaceutical supply chain management startup company who has partnered with several drug manufacturers and aims to provide an open, secure and interoperable network. <ref>MediLedger. (2018). The MediLedger Project. Retrieved from: https://mediledger.com/</ref><br />
<br />
* Drug and Pharmacy Verification - [https://devpost.com/software/veripharm VeriPharm] has developed a proof of concept that would help track and verify pharmaceuticals from the raw materials to the final product administered to patients.<br />
<br />
* Appointment Scheduling on the Blockchain - [https://devpost.com/software/dhva-appointment-blocks dhva-apointment-blocks]<br />
<br />
* Care Coordination - Projects such as [https://devpost.com/software/simplyvitahlth simplyvitahlth] are geared toward coordinating care between multiple providers and at different institutions to ensure that complex care pathways are being followed appropriately.<br />
<br />
<br />
There are many more potential use-cases for blockchain technology within healthcare, and undoubtedly we will continue to see development in this area in coming years. In 2016, a consortium of sponsors led by [https://gem.co/ Gem] (Whitepaper)<ref>Wood C, Winton B, Carter K, Benkert S, Dodd L, Bradley J, et al. How Blockchain Technology Can Enhance Ehr Operability [Internet]. 2016. Available from: http://research.ark-invest.com/blockchain-and-healthcare</ref> held the first healthcare oriented blockchain conference, [https://godistributed.com/health Distributed: Health] in Nashville, TN. Similarly, the Office of the National Coordinator (ONC) Tech Lab had issued a Blockchain Challenge in July, 2016.<ref>https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab</ref><br />
* The list of submissions and awards can be found [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab here]<br />
<br />
As the healthcare blockchain community grows, gatherings such as these will likely increase and blockchain technologies will increasingly be introduced at major medical conferences.<br />
<br />
== References ==<br />
<references /><br />
<br />
Submitted by Sandeep Regmi<br />
[[Category: BMI512-FALL-18]]<br />
<br />
Submitted by Ben Orwoll<br />
<br />
[[Category: BMI512-FALL-16]]<br />
[[Category: Reviews]]<br />
[[Category: Other Technologies]]</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/The_Blockchain_in_HealthcareThe Blockchain in Healthcare2018-10-19T02:48:09Z<p>Phamnh: /* What is the Blockchain? */</p>
<hr />
<div>The blockchain is an idea centered around the concept of a secure, digital ledger system that provides a system for efficient, auditable transactions of almost any type between entities <ref>Tapscott D, Tapscott A. Blockchain Revolution: How the Technology Behind Bitcoin Is Changing Money, Business, and the World. United States: Portfolio; 2016. 1-368 p.</ref>. All information related to blockchain transactions is at once both independently verifiable by all (even outside) parties as correct and also inscrutable to entities without explicit permission. The first and probably most well-known implementation of blockchain technology is [https://bitcoin.org Bitcoin] <ref name="BTC">Nakamoto S. Bitcoin: A Peer-to-Peer Electronic Cash System. WwwBitcoinOrg [Internet]. 2008;9. Available from: https://bitcoin.org/bitcoin.pdf</ref>, but there has been a massive expansion of blockchain use-cases since Bitcoin's initial introduction.<br />
<br />
<br />
<br />
== What is the Blockchain? ==<br />
<br />
First, it should be clear that there is no one blockchain to rule them all. "The Blockchain," as it is often referred, really is a concept of a series (chain) of interrelated sets (blocks) of encrypted information. Hence a chain of blocks, or blockchain. There are many such blockchains in existence, and one could choose to do transactions on any one of them or create a new blockchain.<br />
<br />
<br />
An important aspect of most blockchains is that they are designed to be maintained on a distributed network of multiple nodes. Each node holds a complete copy of the blockchain and adds each sequential new block as it is created. This system allows every transaction on the blockchain to be verified by any or all of the nodes in the network, and also makes it very difficult for the information held in the blockchain to become lost or unavailable if any one or even most of the nodes go offline.<br />
<br />
<br />
Transactions that are set to be added to the blockchain are added to the newest block as soon as it is created. This makes the continued existence of the blockchain dependent on the creation of new blocks. There are several main methods for the creation of new blocks on the network, and the choice of method depends somewhat on the purpose of the blockchain in question. Bitcoin, the first cryptocurrency, uses a method called Proof of Work, but there are at least two methods currently in use:<br />
* [https://en.wikipedia.org/wiki/Proof-of-work_system Proof of Work System (Wikipedia)]<br />
** In the traditional Proof of Work System, each block validator, or "miner," competes to validate the block by processing a task. The winner is the first person to complete this task. The chance of completion of the task is random based on a hash function, but increases with the more "work" a person puts into the task. The system can automatically vary the difficulty of the task to limit the speed of block generation. The winner is credited for his/her work by a small amount of currency. <br />
* [https://en.wikipedia.org/wiki/Proof-of-stake Proof of Stake (Wikipedia)] [https://en.bitcoin.it/wiki/Proof_of_Stake Proof of Stake (Bitcoin Wiki)]<br />
** There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake<ref>Siim, Janno. "Proof-of-Stake."</ref>. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker.<br />
<br />
<br />
The blockchain has moved beyond simply processing transactions of cryptocurrency such as Bitcoin. Any data that can be encoded into a cryptographic [https://en.wikipedia.org/wiki/Hash_function hash] can be added to a blockchain. Various different ideas have been proposed, and I will not attempt to list them here, but they are wide ranging. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0<ref>Swan, M. (2015). Blockchain: Blueprint for a new economy: " O'Reilly Media, Inc."</ref>. Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education.<br />
<br />
<br />
=== Blockchain Development Groups ===<br />
Certainly a non-exhaustive list . . .<br />
<br />
* [https://bitcoin.org/en/ Bitcoin]<br />
<br />
* [https://hyperledger.org The Hyperledger Project]<br />
<br />
* [https://ethereum.org The Ethereum Project]<br />
<br />
* [https://r3cev.com/blog/2016/4/4/introducing-r3-corda-a-distributed-ledger-designed-for-financial-services The CORDA Platform]<br />
<br />
* [http://www.muskokagroup.org/ The Muskoka Group]<br />
<br />
* [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab The ONC Tech Lab]<br />
<br />
== Blockchain Use Cases ==<br />
<br />
=== Cryptocurrency ===<br />
Bitcoin (BTC) was the first cryptocurrency based on the blockchain and was developed by someone calling himself (or herself) Satoshi Nakamoto. The protocol was introduced in 2008 after the publication of a white paper<ref name="BTC" /> describing the algorithm and the mechanisms for generation and distribution of BTC. At this point there are hundreds of cryptocurrencies in circulation according to [http://wikipedia.org Wikipedia], many of which are based on the Bitcoin blockchain, but only a few have gone into widespread use<ref>https://en.wikipedia.org/wiki/List_of_cryptocurrencies</ref>.<br />
<br />
=== Smart Contracts ===<br />
One of the major potential functions of blockchain technology is through the creation of smart contracts. Various components of contracts, including proof of the involved parties, requirements for completion, and actions upon completion of the contract can be encoded in blocks. These can then be added to a blockchain and become available for independent verification, which can even lead to automatic processing of contracts when their requirements have been fulfilled.<br />
<br />
Smart contracts are scripts which have various rules and logic that automatically execute when those rules are met. Smart contracts allow heavily automated workflows between transacting parties in the network while maintaining anonymity. Once the contract has been executed, one can take custody over assets or pre-defined payments can be issued. <ref>Christidis, K & Devetsikiotis, M. (2016, May 10). Blockchains and Smart Contracts for the Internet of Things. IEEE Access, 4, 2292-2303. doi: 10.1109/ACCESS.2016.2566339</ref> They are importantly different in the sense that they are stored on a distributed network and they can be verified as true without knowledge of the contract specifications <ref>https://bitsonblocks.net/2016/02/01/a-gentle-introduction-to-smart-contracts/</ref>.<br />
<br />
[https://ethereum.org The Ethereum Project] was one of the first to introduce the concept of smart contracts using their alternative blockchain and currency token, [https://www.ethereum.org/ether ether].<br />
<br />
=== Securities Exchanges and Finance ===<br />
<br />
One of the hottest arenas for blockchain development currently is in the financial markets, an extension of the original cryptocurrency use cases for the blockchain. Multiple stock markets and other financial firms have initiated investigations and pilot projects into the feasibility and utility of the blockchain for contracts and tracking of financial instruments. NASDAQ has been one of the first major markets to put blockchain technology into use, and has released some information on its implementation, called Linq <ref>http://ir.nasdaq.com/releasedetail.cfm?releaseid=948326</ref><ref>http://www.coindesk.com/hands-on-with-linq-nasdaqs-private-markets-blockchain-project/</ref>. The cryptocurrency website [http://www.coindesk.com Coindesk] has also produced a list of 10 exchanges using or investigating blockchain technologies<ref>http://www.coindesk.com/10-stock-exchanges-blockchain/</ref>.<br />
<br />
<br />
Additionally, financial firms such as Visa have been experimenting with the blockchain for keeping track of transactions as well as with proof of concept applications such as remittance<ref>http://www.coindesk.com/hands-on-with-visa-europes-bitcoin-remittance-app/</ref>.<br />
<br />
== Advantages and Disadvantages of Blockchain ==<br />
<br />
Blockchain is a novel concept and is being explored in various sectors. While there may be several applications and limitations of this technology in future, some of them are highlighted below<ref>Fauvel, W. (2017, August 11). Blockchain Advantage and Disadvantages. Medium. Retrieved from: https://medium.com/nudjed/blockchain-advantage-and-disadvantages-e76dfde3bbc0</ref>:<br />
<br />
=== Pros: ===<br />
# Distributed: There is no single owner of the database. As anyone can contribute and be a part of the network, the risks of data tampering and fraud are minimal. As Nakamoto <ref name="BTC" /> mentioned, as long as the majority of nodes are honest, a random attacker would not be able to alter the history.<br />
# Trustless: As every node in the network will have a copy of the blockchain and they verify the transactions independently. Hence, this system allows transaction even if the parties don't trust each other.<br />
# Immutable: Once the transaction is verified and embedded in the blockchain, it is almost impossible to undo it, and the complexity increases with time as more blocks are added downstream. This allows keeping a track of accurate events that occurred through the history.<br />
# Decentralized: There is no middleman like banks or data owners. This helps avoid manipulation of the market by the owners.<br />
<br />
<br />
=== Cons: ===<br />
# Waste of resources: As several nodes are running and utilizing a huge amount of computing power and electricity to verify and maintain the blockchain, there is more than required redundancy. <br />
# Higher cost for less value: With time, the use of network increases and the complexity of the hashing algorithm also increases. Hence, more resources are required for the same amount of work. This increases the cost of work and transactions gets slower, as miners prioritize the transactions with higher incentives causing a backlog the transactions with smaller values. <br />
# Difficulty to keep up with the size of the block: As the size continues to grow along with the complexity to solve the calculation, new nodes with smaller computing power will have difficulty joining the network and likewise, the older and slower nodes will gradually fade with decreasing incentive for the work. Hence, like Darwin’s theory of the "survival of the fittest", a few larger nodes will dominate the network creating more and more centralization of the system. <br />
# Speculative market: Due to the lack of proper regulation of this system, the market is subject to a great volatility and thus making it risky for investors. <br />
# Immutable smart contracts: As there are clear advantages of having permanent and immutable records, at the same time, there is a bitter flipside to this. For example, if there is a flaw with code that can compromise the system, it is also irreparable and creates the opportunity for the attackers to exploit the same flaw repetitively in future. As time progresses, the capability of repairing the error will be even more complex.<br />
<br />
<br />
<br />
== Potential Use Cases in Healthcare ==<br />
Though there has yet to be a breakthrough report or use-case for blockchain technology in healthcare, there are many potential ways that the blockchain could be implemented within the current healthcare structure. Any list will likely be incomplete, but these examples represent some of the published and available literature on blockchain implementations in health.<br />
<br />
=== Health Information Exchange (HIE) ===<br />
One major area that blockchains may be able to facilitate is the secure access to and communication of patient health records between individuals and institutions. There have been multiple white papers published on the topic, including groups from the Mayo Clinic <ref>Peterson K, Deeduvanu R, Kanjamala P, Boles K. A Blockchain-Based Approach to Health Information Exchange Networks. (1):1–10.</ref> and MIT <ref>Ekblaw A, Azaria A, Halamka JD, Lippman A, Original I, Vieira T. A Case Study for Blockchain in Healthcare: “ MedRec ” prototype for electronic health records and medical research data MedRec: Using Blockchain for Medical Data Access and Permission Management [Internet]. 2016. Available from: https://www.healthit.gov/sites/default/files/5-56-onc_blockchainchallenge_mitwhitepaper.pdf</ref> who described a system for patient information exchange based on blockchain technology that would allow patient-controlled access to records across institutions using HL7 Fast Healthcare Interoperability Resources ([[FHIR]]), [http://json.org JSON], or other encoding system. In these models the actual health care data are not encoded in the blockchain, but are merely references pointing to where the data reside, such as at institutions or in a "data lake" <ref>Linn LA, Koo MB. Blockchain For Health Data and Its Potential Use in Health IT and Health Care Related Research. 2014;1–10.</ref>. Similarly, a group out of China described an app called Healthcare Data Gateway (HGD) that allows patients to view and directly control rule-based access to their health records with a smart phone interface and authentication provided by a blockchain network <ref>Yue X, Wang H, Jin D, Li M, Jiang W. Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst [Internet]. 2016 Oct;40(10):218. Available from: http://dx.doi.org/10.1007/s10916-016-0574-6</ref>. These ideas support the concept of patient-owned medical data, and would have the effect of decentralization of medical records in ways that are as yet undetermined.<br />
<br />
=== Health Research Integrity ===<br />
Academic research is a major driver of advances in health care, but in the setting of limited funding and publication pressures on researchers significant concerns have been raised regarding research integrity<ref>Titus SL, Wells J a, Rhoades LJ. Repairing research integrity. Nature [Internet]. 2008 Jun 19;453(7198):980–2. Available from: http://www.ncbi.nlm.nih.gov/pubmed/18563131</ref>. Organizations such as [http://clinicaltrials.gov ClinicalTrials.gov] and others have been developed to help drive researchers to define endpoints and analysis prior to conducting clinical trials and other studies. As it represents an immutable, verifiable record of events and transactions, the blockchain has been proposed as a potential decentralized resources for helping to ensure biomedical research integrity. Benjamin Carlisle<ref>Carlisle BG. Proof of prespecified endpoints in medical research with the bitcoin blockchain [Internet]. 2014. Available from: http://www.bgcarlisle.com/blog/2014/08/25/proof-of-prespecified-endpoints-in-medical-research-with-the-bitcoin-blockchain/</ref>, followed by several researchers from the UK<ref>Irving G, Holden J. How blockchain-timestamped protocols could improve the trustworthiness of medical science. F1000Research [Internet]. 2016;5:222. Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4866630/</ref>, proposed in 2014 that researchers could use the blockchain to record pre-specified aspects of their projects, including the study design, analysis plan, and data structure, among others, which could later be verified by consumers of the literature to decrease bias that may be introduced in post-hoc analysis<ref>Slade E, Drysdale H, Goldacre B, COMPare Team. Discrepancies Between Prespecified and Reported Outcomes. Ann Intern Med [Internet]. 2016 Mar 1;164(5):374. Available from: http://www.ncbi.nlm.nih.gov/pubmed/26720309</ref>. The blockchain also offers the potential ability to verify the integrity of actual research data and analysis by outside observers, even if the data themselves are not made publicly available. These types of implementations may lead to improvements in both the integrity of biomedical research as well as bolster public trust in medical research.<br />
<br />
=== Personal Health Records ===<br />
This concept dovetails with the idea of HIE using the blockchain, but focuses more on the secure maintenance of a personal health record (PHR) by patients. No production PHR has been released based on this technology, but concepts such as MedVault <ref>Baxendale G. Can Blockchain Revolutionise EPRs? [Internet]. Vol. 58, ITNOW. 2016. p. 38–9. Available from: http://itnow.oxfordjournals.org/lookup/doi/10.1093/itnow/bww017</ref> use alternative blockchains such as [http://www.Colu.com Colu] to store patient data directly on the blockchain. Others such as [https://devpost.com/software/ehealthwallet eHealthWallet] have also developed prototype PHRs based on the blockchain. Patients could then share or authorize doctors and other health entities to access and modify their data.<br />
<br />
=== Storage of Health Care Data ===<br />
Most of the previous examples use the blockchain not as a direct data storage medium, but instead as a secure reference point for identities, access, and data locations. At least one group from a company called Tierion, which partners with the [http://www.2.forms.healthcare.philips.com/blockchainlabs Philips Blockchain Lab ], has produced a concept called Chainpoint<ref>Vaughan AW, Bukowski J, Wilkinson S, Sporny CM, Shea R, Allen C, et al. Chainpoint: A scalable protocol for anchoring data in the blockchain and generating blockchain receipts [Internet]. 2016. Available from: https://tierion.com/chainpoint</ref>, which proposes to use a [https://proofofexistence.com/about Proof of Existence] concept and Merkle Roots<ref>Merkle RC. PROTOCOLS FOR PUBUC KEY CRYPTOSYSTEMS. In: IEEE Symposium on Security and Privacy [Internet]. 1980. p. 122–34. Available from: http://www.merkle.com/papers/Protocols.pdf</ref> to efficiently store actual patient records on the blockchain without imposing excessive transaction demands on the system.<br />
<br />
=== Billing and Claims Adjudication ===<br />
Blockchain system can help reduce administrative costs and time while automating claims adjudication and payment processing using smart contracts. For example - a smart contract is set up between payer or insurance company, provider, and patient such that when the patient sees a provider, or if a procedure is done, an entry is recorded in the blockchain. Based on the criteria set, the contract can automatically issue reimbursement from the payer as well as co-pay from the patient without having to wait for the insurance approval.<ref>Srinivasan, P. (2017, November 9). Healthcare Blockchain: How Smart Contracts Could Revolutionize Care Delivery. Prolifics. Retrieved from: https://www.prolifics.com/blog/healthcare-blockchain-how-smart-contracts-could-revolutionize-care-delivery</ref><br />
<br />
=== Drug Supply Chain and Prescription Management ===<br />
Counterfeit drugs are a major problem especially in the developing country where it is estimated that about 1 in 10 medical products are counterfeit <ref>WHO. (2017, November 28). 1 in 10 medical products in developing countries is substandard or falsified. Retrieved from: http://www.who.int/en/news-room/detail/28-11-2017-1-in-10-medical-products-in-developing-countries-is-substandard-or-falsified</ref>. Ensuring the integrity of the drug and maintaining a robust audit trail is a must to ensure patient safety. Similarly, this platform can be used in prescription drug management and track history and authenticate prescriptions using smart-contracts. <br />
<br />
=== Few Examples of Current Use Cases and Future Development ===<br />
<br />
* MedRec- it is based on Ethereum platform and focuses on medical data management using smart contracts like managing permissions and authentication processes, data sharing in an interoperable environment between healthcare systems and maintaining an audit log. <ref>Azaria, A., Ekblaw, A., Vieira, T., & Lippman, A. (2016, August 22-24). MedRec: Using Blockchain for Medical Data Access and Permission Management. 2016 2nd International Conference on Open and Big Data (OBD). doi:10.1109/obd.2016.11</ref><br />
<br />
* Guardtime- also focuses on medical data management and has partnered with e-Health authority of Estonia to secure the country's database of health records <ref>Ruubel M. (2016, February 12). Estonian eHealth Authority Partners with Guardtime to Accelerate Transparency and Auditability in Health Care. Retrieved from: https://guardtime.com/blog/estonian-ehealth-partners-guardtime-blockchain-based-transparency</ref>. Also, recently, MyPCR smartphone platform from Guardtime has partnered with Instant Access Medical and Healthcare Gateway in the UK for patient health data management and verification of medication adherence. <ref>Ruubel M. (2018, June 20). World’s first blockchain-supported Personal Care Record Platform launched by Guardtime and partners to up to 30 million NHS patients in the UK. Retrieved from: https://guardtime.com/blog/world-s-first-blockchain-supported-personal-care-record-platform-launched-by-guardtime-and-partners</ref> <br />
<br />
* Blockchain Health- created for healthcare research data management where users can individually authorize the release of their health information to researchers as well as track the use of their data. <ref>BlockchainHealth. (2016). Blockchain for health research. Retrieved from: https://blockchainhealth.co/</ref><br />
<br />
* BlockMedx- it is a startup company which intends to use the blockchain platform to transmit DEA controlled drug prescriptions from physicians to pharmacies and then to patients securely. <ref>BlockMedx. (2018). Retrieved from: https://blockmedx.com/en/</ref><br />
<br />
* MediLedger- another pharmaceutical supply chain management startup company who has partnered with several drug manufacturers and aims to provide an open, secure and interoperable network. <ref>MediLedger. (2018). The MediLedger Project. Retrieved from: https://mediledger.com/</ref><br />
<br />
* Drug and Pharmacy Verification - [https://devpost.com/software/veripharm VeriPharm] has developed a proof of concept that would help track and verify pharmaceuticals from the raw materials to the final product administered to patients.<br />
<br />
* Appointment Scheduling on the Blockchain - [https://devpost.com/software/dhva-appointment-blocks dhva-apointment-blocks]<br />
<br />
* Care Coordination - Projects such as [https://devpost.com/software/simplyvitahlth simplyvitahlth] are geared toward coordinating care between multiple providers and at different institutions to ensure that complex care pathways are being followed appropriately.<br />
<br />
<br />
There are many more potential use-cases for blockchain technology within healthcare, and undoubtedly we will continue to see development in this area in coming years. In 2016, a consortium of sponsors led by [https://gem.co/ Gem] (Whitepaper)<ref>Wood C, Winton B, Carter K, Benkert S, Dodd L, Bradley J, et al. How Blockchain Technology Can Enhance Ehr Operability [Internet]. 2016. Available from: http://research.ark-invest.com/blockchain-and-healthcare</ref> held the first healthcare oriented blockchain conference, [https://godistributed.com/health Distributed: Health] in Nashville, TN. Similarly, the Office of the National Coordinator (ONC) Tech Lab had issued a Blockchain Challenge in July, 2016.<ref>https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab</ref><br />
* The list of submissions and awards can be found [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab here]<br />
<br />
As the healthcare blockchain community grows, gatherings such as these will likely increase and blockchain technologies will increasingly be introduced at major medical conferences.<br />
<br />
== References ==<br />
<references /><br />
<br />
Submitted by Sandeep Regmi<br />
[[Category: BMI512-FALL-18]]<br />
<br />
Submitted by Ben Orwoll<br />
<br />
[[Category: BMI512-FALL-16]]<br />
[[Category: Reviews]]<br />
[[Category: Other Technologies]]</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/The_Blockchain_in_HealthcareThe Blockchain in Healthcare2018-10-19T02:46:37Z<p>Phamnh: /* What is the Blockchain? */</p>
<hr />
<div>The blockchain is an idea centered around the concept of a secure, digital ledger system that provides a system for efficient, auditable transactions of almost any type between entities <ref>Tapscott D, Tapscott A. Blockchain Revolution: How the Technology Behind Bitcoin Is Changing Money, Business, and the World. United States: Portfolio; 2016. 1-368 p.</ref>. All information related to blockchain transactions is at once both independently verifiable by all (even outside) parties as correct and also inscrutable to entities without explicit permission. The first and probably most well-known implementation of blockchain technology is [https://bitcoin.org Bitcoin] <ref name="BTC">Nakamoto S. Bitcoin: A Peer-to-Peer Electronic Cash System. WwwBitcoinOrg [Internet]. 2008;9. Available from: https://bitcoin.org/bitcoin.pdf</ref>, but there has been a massive expansion of blockchain use-cases since Bitcoin's initial introduction.<br />
<br />
<br />
<br />
== What is the Blockchain? ==<br />
<br />
First, it should be clear that there is no one blockchain to rule them all. "The Blockchain," as it is often referred, really is a concept of a series (chain) of interrelated sets (blocks) of encrypted information. Hence a chain of blocks, or blockchain. There are many such blockchains in existence, and one could choose to do transactions on any one of them or create a new blockchain.<br />
<br />
<br />
An important aspect of most blockchains is that they are designed to be maintained on a distributed network of multiple nodes. Each node holds a complete copy of the blockchain and adds each sequential new block as it is created. This system allows every transaction on the blockchain to be verified by any or all of the nodes in the network, and also makes it very difficult for the information held in the blockchain to become lost or unavailable if any one or even most of the nodes go offline.<br />
<br />
<br />
Transactions that are set to be added to the blockchain are added to the newest block as soon as it is created. This makes the continued existence of the blockchain dependent on the creation of new blocks. There are several main methods for the creation of new blocks on the network, and the choice of method depends somewhat on the purpose of the blockchain in question. Bitcoin, the first cryptocurrency, uses a method called Proof of Work, but there are at least two methods currently in use:<br />
* [https://en.wikipedia.org/wiki/Proof-of-work_system Proof of Work System (Wikipedia)]<br />
** In the traditional Proof of Work System, each block validator, or "miner," competes to validate the block by processing a task. The winner is the first person to complete this task. The chance of completion of the task is random based on a hash function, but increases with the more "work" a person puts into the task. The system can automatically vary the difficulty of the task to limit the speed of block generation. The winner is credited for his/her work by a small amount of currency. <br />
* [https://en.wikipedia.org/wiki/Proof-of-stake Proof of Stake (Wikipedia)] [https://en.bitcoin.it/wiki/Proof_of_Stake Proof of Stake (Bitcoin Wiki)]<br />
** There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake<ref>Siim, Janno. "Proof-of-Stake."</ref>. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker.<br />
<br />
<br />
The blockchain has moved beyond simply processing transactions of cryptocurrency such as Bitcoin. Any data that can be encoded into a cryptographic [https://en.wikipedia.org/wiki/Hash_function hash] can be added to a blockchain. Various different ideas have been proposed, and I will not attempt to list them here, but they are wide ranging.<br />
<br />
<br />
=== Blockchain Development Groups ===<br />
Certainly a non-exhaustive list . . .<br />
<br />
* [https://bitcoin.org/en/ Bitcoin]<br />
<br />
* [https://hyperledger.org The Hyperledger Project]<br />
<br />
* [https://ethereum.org The Ethereum Project]<br />
<br />
* [https://r3cev.com/blog/2016/4/4/introducing-r3-corda-a-distributed-ledger-designed-for-financial-services The CORDA Platform]<br />
<br />
* [http://www.muskokagroup.org/ The Muskoka Group]<br />
<br />
* [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab The ONC Tech Lab]<br />
<br />
== Blockchain Use Cases ==<br />
<br />
=== Cryptocurrency ===<br />
Bitcoin (BTC) was the first cryptocurrency based on the blockchain and was developed by someone calling himself (or herself) Satoshi Nakamoto. The protocol was introduced in 2008 after the publication of a white paper<ref name="BTC" /> describing the algorithm and the mechanisms for generation and distribution of BTC. At this point there are hundreds of cryptocurrencies in circulation according to [http://wikipedia.org Wikipedia], many of which are based on the Bitcoin blockchain, but only a few have gone into widespread use<ref>https://en.wikipedia.org/wiki/List_of_cryptocurrencies</ref>.<br />
<br />
=== Smart Contracts ===<br />
One of the major potential functions of blockchain technology is through the creation of smart contracts. Various components of contracts, including proof of the involved parties, requirements for completion, and actions upon completion of the contract can be encoded in blocks. These can then be added to a blockchain and become available for independent verification, which can even lead to automatic processing of contracts when their requirements have been fulfilled.<br />
<br />
Smart contracts are scripts which have various rules and logic that automatically execute when those rules are met. Smart contracts allow heavily automated workflows between transacting parties in the network while maintaining anonymity. Once the contract has been executed, one can take custody over assets or pre-defined payments can be issued. <ref>Christidis, K & Devetsikiotis, M. (2016, May 10). Blockchains and Smart Contracts for the Internet of Things. IEEE Access, 4, 2292-2303. doi: 10.1109/ACCESS.2016.2566339</ref> They are importantly different in the sense that they are stored on a distributed network and they can be verified as true without knowledge of the contract specifications <ref>https://bitsonblocks.net/2016/02/01/a-gentle-introduction-to-smart-contracts/</ref>.<br />
<br />
[https://ethereum.org The Ethereum Project] was one of the first to introduce the concept of smart contracts using their alternative blockchain and currency token, [https://www.ethereum.org/ether ether].<br />
<br />
=== Securities Exchanges and Finance ===<br />
<br />
One of the hottest arenas for blockchain development currently is in the financial markets, an extension of the original cryptocurrency use cases for the blockchain. Multiple stock markets and other financial firms have initiated investigations and pilot projects into the feasibility and utility of the blockchain for contracts and tracking of financial instruments. NASDAQ has been one of the first major markets to put blockchain technology into use, and has released some information on its implementation, called Linq <ref>http://ir.nasdaq.com/releasedetail.cfm?releaseid=948326</ref><ref>http://www.coindesk.com/hands-on-with-linq-nasdaqs-private-markets-blockchain-project/</ref>. The cryptocurrency website [http://www.coindesk.com Coindesk] has also produced a list of 10 exchanges using or investigating blockchain technologies<ref>http://www.coindesk.com/10-stock-exchanges-blockchain/</ref>.<br />
<br />
<br />
Additionally, financial firms such as Visa have been experimenting with the blockchain for keeping track of transactions as well as with proof of concept applications such as remittance<ref>http://www.coindesk.com/hands-on-with-visa-europes-bitcoin-remittance-app/</ref>.<br />
<br />
== Advantages and Disadvantages of Blockchain ==<br />
<br />
Blockchain is a novel concept and is being explored in various sectors. While there may be several applications and limitations of this technology in future, some of them are highlighted below<ref>Fauvel, W. (2017, August 11). Blockchain Advantage and Disadvantages. Medium. Retrieved from: https://medium.com/nudjed/blockchain-advantage-and-disadvantages-e76dfde3bbc0</ref>:<br />
<br />
=== Pros: ===<br />
# Distributed: There is no single owner of the database. As anyone can contribute and be a part of the network, the risks of data tampering and fraud are minimal. As Nakamoto <ref name="BTC" /> mentioned, as long as the majority of nodes are honest, a random attacker would not be able to alter the history.<br />
# Trustless: As every node in the network will have a copy of the blockchain and they verify the transactions independently. Hence, this system allows transaction even if the parties don't trust each other.<br />
# Immutable: Once the transaction is verified and embedded in the blockchain, it is almost impossible to undo it, and the complexity increases with time as more blocks are added downstream. This allows keeping a track of accurate events that occurred through the history.<br />
# Decentralized: There is no middleman like banks or data owners. This helps avoid manipulation of the market by the owners.<br />
<br />
<br />
=== Cons: ===<br />
# Waste of resources: As several nodes are running and utilizing a huge amount of computing power and electricity to verify and maintain the blockchain, there is more than required redundancy. <br />
# Higher cost for less value: With time, the use of network increases and the complexity of the hashing algorithm also increases. Hence, more resources are required for the same amount of work. This increases the cost of work and transactions gets slower, as miners prioritize the transactions with higher incentives causing a backlog the transactions with smaller values. <br />
# Difficulty to keep up with the size of the block: As the size continues to grow along with the complexity to solve the calculation, new nodes with smaller computing power will have difficulty joining the network and likewise, the older and slower nodes will gradually fade with decreasing incentive for the work. Hence, like Darwin’s theory of the "survival of the fittest", a few larger nodes will dominate the network creating more and more centralization of the system. <br />
# Speculative market: Due to the lack of proper regulation of this system, the market is subject to a great volatility and thus making it risky for investors. <br />
# Immutable smart contracts: As there are clear advantages of having permanent and immutable records, at the same time, there is a bitter flipside to this. For example, if there is a flaw with code that can compromise the system, it is also irreparable and creates the opportunity for the attackers to exploit the same flaw repetitively in future. As time progresses, the capability of repairing the error will be even more complex.<br />
<br />
<br />
<br />
== Potential Use Cases in Healthcare ==<br />
Though there has yet to be a breakthrough report or use-case for blockchain technology in healthcare, there are many potential ways that the blockchain could be implemented within the current healthcare structure. Any list will likely be incomplete, but these examples represent some of the published and available literature on blockchain implementations in health.<br />
<br />
=== Health Information Exchange (HIE) ===<br />
One major area that blockchains may be able to facilitate is the secure access to and communication of patient health records between individuals and institutions. There have been multiple white papers published on the topic, including groups from the Mayo Clinic <ref>Peterson K, Deeduvanu R, Kanjamala P, Boles K. A Blockchain-Based Approach to Health Information Exchange Networks. (1):1–10.</ref> and MIT <ref>Ekblaw A, Azaria A, Halamka JD, Lippman A, Original I, Vieira T. A Case Study for Blockchain in Healthcare: “ MedRec ” prototype for electronic health records and medical research data MedRec: Using Blockchain for Medical Data Access and Permission Management [Internet]. 2016. Available from: https://www.healthit.gov/sites/default/files/5-56-onc_blockchainchallenge_mitwhitepaper.pdf</ref> who described a system for patient information exchange based on blockchain technology that would allow patient-controlled access to records across institutions using HL7 Fast Healthcare Interoperability Resources ([[FHIR]]), [http://json.org JSON], or other encoding system. In these models the actual health care data are not encoded in the blockchain, but are merely references pointing to where the data reside, such as at institutions or in a "data lake" <ref>Linn LA, Koo MB. Blockchain For Health Data and Its Potential Use in Health IT and Health Care Related Research. 2014;1–10.</ref>. Similarly, a group out of China described an app called Healthcare Data Gateway (HGD) that allows patients to view and directly control rule-based access to their health records with a smart phone interface and authentication provided by a blockchain network <ref>Yue X, Wang H, Jin D, Li M, Jiang W. Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst [Internet]. 2016 Oct;40(10):218. Available from: http://dx.doi.org/10.1007/s10916-016-0574-6</ref>. These ideas support the concept of patient-owned medical data, and would have the effect of decentralization of medical records in ways that are as yet undetermined.<br />
<br />
=== Health Research Integrity ===<br />
Academic research is a major driver of advances in health care, but in the setting of limited funding and publication pressures on researchers significant concerns have been raised regarding research integrity<ref>Titus SL, Wells J a, Rhoades LJ. Repairing research integrity. Nature [Internet]. 2008 Jun 19;453(7198):980–2. Available from: http://www.ncbi.nlm.nih.gov/pubmed/18563131</ref>. Organizations such as [http://clinicaltrials.gov ClinicalTrials.gov] and others have been developed to help drive researchers to define endpoints and analysis prior to conducting clinical trials and other studies. As it represents an immutable, verifiable record of events and transactions, the blockchain has been proposed as a potential decentralized resources for helping to ensure biomedical research integrity. Benjamin Carlisle<ref>Carlisle BG. Proof of prespecified endpoints in medical research with the bitcoin blockchain [Internet]. 2014. Available from: http://www.bgcarlisle.com/blog/2014/08/25/proof-of-prespecified-endpoints-in-medical-research-with-the-bitcoin-blockchain/</ref>, followed by several researchers from the UK<ref>Irving G, Holden J. How blockchain-timestamped protocols could improve the trustworthiness of medical science. F1000Research [Internet]. 2016;5:222. Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4866630/</ref>, proposed in 2014 that researchers could use the blockchain to record pre-specified aspects of their projects, including the study design, analysis plan, and data structure, among others, which could later be verified by consumers of the literature to decrease bias that may be introduced in post-hoc analysis<ref>Slade E, Drysdale H, Goldacre B, COMPare Team. Discrepancies Between Prespecified and Reported Outcomes. Ann Intern Med [Internet]. 2016 Mar 1;164(5):374. Available from: http://www.ncbi.nlm.nih.gov/pubmed/26720309</ref>. The blockchain also offers the potential ability to verify the integrity of actual research data and analysis by outside observers, even if the data themselves are not made publicly available. These types of implementations may lead to improvements in both the integrity of biomedical research as well as bolster public trust in medical research.<br />
<br />
=== Personal Health Records ===<br />
This concept dovetails with the idea of HIE using the blockchain, but focuses more on the secure maintenance of a personal health record (PHR) by patients. No production PHR has been released based on this technology, but concepts such as MedVault <ref>Baxendale G. Can Blockchain Revolutionise EPRs? [Internet]. Vol. 58, ITNOW. 2016. p. 38–9. Available from: http://itnow.oxfordjournals.org/lookup/doi/10.1093/itnow/bww017</ref> use alternative blockchains such as [http://www.Colu.com Colu] to store patient data directly on the blockchain. Others such as [https://devpost.com/software/ehealthwallet eHealthWallet] have also developed prototype PHRs based on the blockchain. Patients could then share or authorize doctors and other health entities to access and modify their data.<br />
<br />
=== Storage of Health Care Data ===<br />
Most of the previous examples use the blockchain not as a direct data storage medium, but instead as a secure reference point for identities, access, and data locations. At least one group from a company called Tierion, which partners with the [http://www.2.forms.healthcare.philips.com/blockchainlabs Philips Blockchain Lab ], has produced a concept called Chainpoint<ref>Vaughan AW, Bukowski J, Wilkinson S, Sporny CM, Shea R, Allen C, et al. Chainpoint: A scalable protocol for anchoring data in the blockchain and generating blockchain receipts [Internet]. 2016. Available from: https://tierion.com/chainpoint</ref>, which proposes to use a [https://proofofexistence.com/about Proof of Existence] concept and Merkle Roots<ref>Merkle RC. PROTOCOLS FOR PUBUC KEY CRYPTOSYSTEMS. In: IEEE Symposium on Security and Privacy [Internet]. 1980. p. 122–34. Available from: http://www.merkle.com/papers/Protocols.pdf</ref> to efficiently store actual patient records on the blockchain without imposing excessive transaction demands on the system.<br />
<br />
=== Billing and Claims Adjudication ===<br />
Blockchain system can help reduce administrative costs and time while automating claims adjudication and payment processing using smart contracts. For example - a smart contract is set up between payer or insurance company, provider, and patient such that when the patient sees a provider, or if a procedure is done, an entry is recorded in the blockchain. Based on the criteria set, the contract can automatically issue reimbursement from the payer as well as co-pay from the patient without having to wait for the insurance approval.<ref>Srinivasan, P. (2017, November 9). Healthcare Blockchain: How Smart Contracts Could Revolutionize Care Delivery. Prolifics. Retrieved from: https://www.prolifics.com/blog/healthcare-blockchain-how-smart-contracts-could-revolutionize-care-delivery</ref><br />
<br />
=== Drug Supply Chain and Prescription Management ===<br />
Counterfeit drugs are a major problem especially in the developing country where it is estimated that about 1 in 10 medical products are counterfeit <ref>WHO. (2017, November 28). 1 in 10 medical products in developing countries is substandard or falsified. Retrieved from: http://www.who.int/en/news-room/detail/28-11-2017-1-in-10-medical-products-in-developing-countries-is-substandard-or-falsified</ref>. Ensuring the integrity of the drug and maintaining a robust audit trail is a must to ensure patient safety. Similarly, this platform can be used in prescription drug management and track history and authenticate prescriptions using smart-contracts. <br />
<br />
=== Few Examples of Current Use Cases and Future Development ===<br />
<br />
* MedRec- it is based on Ethereum platform and focuses on medical data management using smart contracts like managing permissions and authentication processes, data sharing in an interoperable environment between healthcare systems and maintaining an audit log. <ref>Azaria, A., Ekblaw, A., Vieira, T., & Lippman, A. (2016, August 22-24). MedRec: Using Blockchain for Medical Data Access and Permission Management. 2016 2nd International Conference on Open and Big Data (OBD). doi:10.1109/obd.2016.11</ref><br />
<br />
* Guardtime- also focuses on medical data management and has partnered with e-Health authority of Estonia to secure the country's database of health records <ref>Ruubel M. (2016, February 12). Estonian eHealth Authority Partners with Guardtime to Accelerate Transparency and Auditability in Health Care. Retrieved from: https://guardtime.com/blog/estonian-ehealth-partners-guardtime-blockchain-based-transparency</ref>. Also, recently, MyPCR smartphone platform from Guardtime has partnered with Instant Access Medical and Healthcare Gateway in the UK for patient health data management and verification of medication adherence. <ref>Ruubel M. (2018, June 20). World’s first blockchain-supported Personal Care Record Platform launched by Guardtime and partners to up to 30 million NHS patients in the UK. Retrieved from: https://guardtime.com/blog/world-s-first-blockchain-supported-personal-care-record-platform-launched-by-guardtime-and-partners</ref> <br />
<br />
* Blockchain Health- created for healthcare research data management where users can individually authorize the release of their health information to researchers as well as track the use of their data. <ref>BlockchainHealth. (2016). Blockchain for health research. Retrieved from: https://blockchainhealth.co/</ref><br />
<br />
* BlockMedx- it is a startup company which intends to use the blockchain platform to transmit DEA controlled drug prescriptions from physicians to pharmacies and then to patients securely. <ref>BlockMedx. (2018). Retrieved from: https://blockmedx.com/en/</ref><br />
<br />
* MediLedger- another pharmaceutical supply chain management startup company who has partnered with several drug manufacturers and aims to provide an open, secure and interoperable network. <ref>MediLedger. (2018). The MediLedger Project. Retrieved from: https://mediledger.com/</ref><br />
<br />
* Drug and Pharmacy Verification - [https://devpost.com/software/veripharm VeriPharm] has developed a proof of concept that would help track and verify pharmaceuticals from the raw materials to the final product administered to patients.<br />
<br />
* Appointment Scheduling on the Blockchain - [https://devpost.com/software/dhva-appointment-blocks dhva-apointment-blocks]<br />
<br />
* Care Coordination - Projects such as [https://devpost.com/software/simplyvitahlth simplyvitahlth] are geared toward coordinating care between multiple providers and at different institutions to ensure that complex care pathways are being followed appropriately.<br />
<br />
<br />
There are many more potential use-cases for blockchain technology within healthcare, and undoubtedly we will continue to see development in this area in coming years. In 2016, a consortium of sponsors led by [https://gem.co/ Gem] (Whitepaper)<ref>Wood C, Winton B, Carter K, Benkert S, Dodd L, Bradley J, et al. How Blockchain Technology Can Enhance Ehr Operability [Internet]. 2016. Available from: http://research.ark-invest.com/blockchain-and-healthcare</ref> held the first healthcare oriented blockchain conference, [https://godistributed.com/health Distributed: Health] in Nashville, TN. Similarly, the Office of the National Coordinator (ONC) Tech Lab had issued a Blockchain Challenge in July, 2016.<ref>https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab</ref><br />
* The list of submissions and awards can be found [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab here]<br />
<br />
As the healthcare blockchain community grows, gatherings such as these will likely increase and blockchain technologies will increasingly be introduced at major medical conferences.<br />
<br />
== References ==<br />
<references /><br />
<br />
Submitted by Sandeep Regmi<br />
[[Category: BMI512-FALL-18]]<br />
<br />
Submitted by Ben Orwoll<br />
<br />
[[Category: BMI512-FALL-16]]<br />
[[Category: Reviews]]<br />
[[Category: Other Technologies]]</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/The_Blockchain_in_HealthcareThe Blockchain in Healthcare2018-10-19T02:38:27Z<p>Phamnh: /* What is the Blockchain? */</p>
<hr />
<div>The blockchain is an idea centered around the concept of a secure, digital ledger system that provides a system for efficient, auditable transactions of almost any type between entities <ref>Tapscott D, Tapscott A. Blockchain Revolution: How the Technology Behind Bitcoin Is Changing Money, Business, and the World. United States: Portfolio; 2016. 1-368 p.</ref>. All information related to blockchain transactions is at once both independently verifiable by all (even outside) parties as correct and also inscrutable to entities without explicit permission. The first and probably most well-known implementation of blockchain technology is [https://bitcoin.org Bitcoin] <ref name="BTC">Nakamoto S. Bitcoin: A Peer-to-Peer Electronic Cash System. WwwBitcoinOrg [Internet]. 2008;9. Available from: https://bitcoin.org/bitcoin.pdf</ref>, but there has been a massive expansion of blockchain use-cases since Bitcoin's initial introduction.<br />
<br />
<br />
<br />
== What is the Blockchain? ==<br />
<br />
First, it should be clear that there is no one blockchain to rule them all. "The Blockchain," as it is often referred, really is a concept of a series (chain) of interrelated sets (blocks) of encrypted information. Hence a chain of blocks, or blockchain. There are many such blockchains in existence, and one could choose to do transactions on any one of them or create a new blockchain.<br />
<br />
<br />
An important aspect of most blockchains is that they are designed to be maintained on a distributed network of multiple nodes. Each node holds a complete copy of the blockchain and adds each sequential new block as it is created. This system allows every transaction on the blockchain to be verified by any or all of the nodes in the network, and also makes it very difficult for the information held in the blockchain to become lost or unavailable if any one or even most of the nodes go offline.<br />
<br />
<br />
Transactions that are set to be added to the blockchain are added to the newest block as soon as it is created. This makes the continued existence of the blockchain dependent on the creation of new blocks. There are several main methods for the creation of new blocks on the network, and the choice of method depends somewhat on the purpose of the blockchain in question. Bitcoin, the first cryptocurrency, uses a method called Proof of Work, but there are at least two methods currently in use:<br />
* [https://en.wikipedia.org/wiki/Proof-of-work_system Proof of Work System (Wikipedia)]<br />
* [https://en.wikipedia.org/wiki/Proof-of-stake Proof of Stake (Wikipedia)] [https://en.bitcoin.it/wiki/Proof_of_Stake Proof of Stake (Bitcoin Wiki)]<br />
** There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake<ref>Siim, Janno. "Proof-of-Stake."</ref>. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker.<br />
<br />
<br />
The blockchain has moved beyond simply processing transactions of cryptocurrency such as Bitcoin. Any data that can be encoded into a cryptographic [https://en.wikipedia.org/wiki/Hash_function hash] can be added to a blockchain. Various different ideas have been proposed, and I will not attempt to list them here, but they are wide ranging.<br />
<br />
<br />
=== Blockchain Development Groups ===<br />
Certainly a non-exhaustive list . . .<br />
<br />
* [https://bitcoin.org/en/ Bitcoin]<br />
<br />
* [https://hyperledger.org The Hyperledger Project]<br />
<br />
* [https://ethereum.org The Ethereum Project]<br />
<br />
* [https://r3cev.com/blog/2016/4/4/introducing-r3-corda-a-distributed-ledger-designed-for-financial-services The CORDA Platform]<br />
<br />
* [http://www.muskokagroup.org/ The Muskoka Group]<br />
<br />
* [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab The ONC Tech Lab]<br />
<br />
== Blockchain Use Cases ==<br />
<br />
=== Cryptocurrency ===<br />
Bitcoin (BTC) was the first cryptocurrency based on the blockchain and was developed by someone calling himself (or herself) Satoshi Nakamoto. The protocol was introduced in 2008 after the publication of a white paper<ref name="BTC" /> describing the algorithm and the mechanisms for generation and distribution of BTC. At this point there are hundreds of cryptocurrencies in circulation according to [http://wikipedia.org Wikipedia], many of which are based on the Bitcoin blockchain, but only a few have gone into widespread use<ref>https://en.wikipedia.org/wiki/List_of_cryptocurrencies</ref>.<br />
<br />
=== Smart Contracts ===<br />
One of the major potential functions of blockchain technology is through the creation of smart contracts. Various components of contracts, including proof of the involved parties, requirements for completion, and actions upon completion of the contract can be encoded in blocks. These can then be added to a blockchain and become available for independent verification, which can even lead to automatic processing of contracts when their requirements have been fulfilled.<br />
<br />
Smart contracts are scripts which have various rules and logic that automatically execute when those rules are met. Smart contracts allow heavily automated workflows between transacting parties in the network while maintaining anonymity. Once the contract has been executed, one can take custody over assets or pre-defined payments can be issued. <ref>Christidis, K & Devetsikiotis, M. (2016, May 10). Blockchains and Smart Contracts for the Internet of Things. IEEE Access, 4, 2292-2303. doi: 10.1109/ACCESS.2016.2566339</ref> They are importantly different in the sense that they are stored on a distributed network and they can be verified as true without knowledge of the contract specifications <ref>https://bitsonblocks.net/2016/02/01/a-gentle-introduction-to-smart-contracts/</ref>.<br />
<br />
[https://ethereum.org The Ethereum Project] was one of the first to introduce the concept of smart contracts using their alternative blockchain and currency token, [https://www.ethereum.org/ether ether].<br />
<br />
=== Securities Exchanges and Finance ===<br />
<br />
One of the hottest arenas for blockchain development currently is in the financial markets, an extension of the original cryptocurrency use cases for the blockchain. Multiple stock markets and other financial firms have initiated investigations and pilot projects into the feasibility and utility of the blockchain for contracts and tracking of financial instruments. NASDAQ has been one of the first major markets to put blockchain technology into use, and has released some information on its implementation, called Linq <ref>http://ir.nasdaq.com/releasedetail.cfm?releaseid=948326</ref><ref>http://www.coindesk.com/hands-on-with-linq-nasdaqs-private-markets-blockchain-project/</ref>. The cryptocurrency website [http://www.coindesk.com Coindesk] has also produced a list of 10 exchanges using or investigating blockchain technologies<ref>http://www.coindesk.com/10-stock-exchanges-blockchain/</ref>.<br />
<br />
<br />
Additionally, financial firms such as Visa have been experimenting with the blockchain for keeping track of transactions as well as with proof of concept applications such as remittance<ref>http://www.coindesk.com/hands-on-with-visa-europes-bitcoin-remittance-app/</ref>.<br />
<br />
== Advantages and Disadvantages of Blockchain ==<br />
<br />
Blockchain is a novel concept and is being explored in various sectors. While there may be several applications and limitations of this technology in future, some of them are highlighted below<ref>Fauvel, W. (2017, August 11). Blockchain Advantage and Disadvantages. Medium. Retrieved from: https://medium.com/nudjed/blockchain-advantage-and-disadvantages-e76dfde3bbc0</ref>:<br />
<br />
=== Pros: ===<br />
# Distributed: There is no single owner of the database. As anyone can contribute and be a part of the network, the risks of data tampering and fraud are minimal. As Nakamoto <ref name="BTC" /> mentioned, as long as the majority of nodes are honest, a random attacker would not be able to alter the history.<br />
# Trustless: As every node in the network will have a copy of the blockchain and they verify the transactions independently. Hence, this system allows transaction even if the parties don't trust each other.<br />
# Immutable: Once the transaction is verified and embedded in the blockchain, it is almost impossible to undo it, and the complexity increases with time as more blocks are added downstream. This allows keeping a track of accurate events that occurred through the history.<br />
# Decentralized: There is no middleman like banks or data owners. This helps avoid manipulation of the market by the owners.<br />
<br />
<br />
=== Cons: ===<br />
# Waste of resources: As several nodes are running and utilizing a huge amount of computing power and electricity to verify and maintain the blockchain, there is more than required redundancy. <br />
# Higher cost for less value: With time, the use of network increases and the complexity of the hashing algorithm also increases. Hence, more resources are required for the same amount of work. This increases the cost of work and transactions gets slower, as miners prioritize the transactions with higher incentives causing a backlog the transactions with smaller values. <br />
# Difficulty to keep up with the size of the block: As the size continues to grow along with the complexity to solve the calculation, new nodes with smaller computing power will have difficulty joining the network and likewise, the older and slower nodes will gradually fade with decreasing incentive for the work. Hence, like Darwin’s theory of the "survival of the fittest", a few larger nodes will dominate the network creating more and more centralization of the system. <br />
# Speculative market: Due to the lack of proper regulation of this system, the market is subject to a great volatility and thus making it risky for investors. <br />
# Immutable smart contracts: As there are clear advantages of having permanent and immutable records, at the same time, there is a bitter flipside to this. For example, if there is a flaw with code that can compromise the system, it is also irreparable and creates the opportunity for the attackers to exploit the same flaw repetitively in future. As time progresses, the capability of repairing the error will be even more complex.<br />
<br />
<br />
<br />
== Potential Use Cases in Healthcare ==<br />
Though there has yet to be a breakthrough report or use-case for blockchain technology in healthcare, there are many potential ways that the blockchain could be implemented within the current healthcare structure. Any list will likely be incomplete, but these examples represent some of the published and available literature on blockchain implementations in health.<br />
<br />
=== Health Information Exchange (HIE) ===<br />
One major area that blockchains may be able to facilitate is the secure access to and communication of patient health records between individuals and institutions. There have been multiple white papers published on the topic, including groups from the Mayo Clinic <ref>Peterson K, Deeduvanu R, Kanjamala P, Boles K. A Blockchain-Based Approach to Health Information Exchange Networks. (1):1–10.</ref> and MIT <ref>Ekblaw A, Azaria A, Halamka JD, Lippman A, Original I, Vieira T. A Case Study for Blockchain in Healthcare: “ MedRec ” prototype for electronic health records and medical research data MedRec: Using Blockchain for Medical Data Access and Permission Management [Internet]. 2016. Available from: https://www.healthit.gov/sites/default/files/5-56-onc_blockchainchallenge_mitwhitepaper.pdf</ref> who described a system for patient information exchange based on blockchain technology that would allow patient-controlled access to records across institutions using HL7 Fast Healthcare Interoperability Resources ([[FHIR]]), [http://json.org JSON], or other encoding system. In these models the actual health care data are not encoded in the blockchain, but are merely references pointing to where the data reside, such as at institutions or in a "data lake" <ref>Linn LA, Koo MB. Blockchain For Health Data and Its Potential Use in Health IT and Health Care Related Research. 2014;1–10.</ref>. Similarly, a group out of China described an app called Healthcare Data Gateway (HGD) that allows patients to view and directly control rule-based access to their health records with a smart phone interface and authentication provided by a blockchain network <ref>Yue X, Wang H, Jin D, Li M, Jiang W. Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst [Internet]. 2016 Oct;40(10):218. Available from: http://dx.doi.org/10.1007/s10916-016-0574-6</ref>. These ideas support the concept of patient-owned medical data, and would have the effect of decentralization of medical records in ways that are as yet undetermined.<br />
<br />
=== Health Research Integrity ===<br />
Academic research is a major driver of advances in health care, but in the setting of limited funding and publication pressures on researchers significant concerns have been raised regarding research integrity<ref>Titus SL, Wells J a, Rhoades LJ. Repairing research integrity. Nature [Internet]. 2008 Jun 19;453(7198):980–2. Available from: http://www.ncbi.nlm.nih.gov/pubmed/18563131</ref>. Organizations such as [http://clinicaltrials.gov ClinicalTrials.gov] and others have been developed to help drive researchers to define endpoints and analysis prior to conducting clinical trials and other studies. As it represents an immutable, verifiable record of events and transactions, the blockchain has been proposed as a potential decentralized resources for helping to ensure biomedical research integrity. Benjamin Carlisle<ref>Carlisle BG. Proof of prespecified endpoints in medical research with the bitcoin blockchain [Internet]. 2014. Available from: http://www.bgcarlisle.com/blog/2014/08/25/proof-of-prespecified-endpoints-in-medical-research-with-the-bitcoin-blockchain/</ref>, followed by several researchers from the UK<ref>Irving G, Holden J. How blockchain-timestamped protocols could improve the trustworthiness of medical science. F1000Research [Internet]. 2016;5:222. Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4866630/</ref>, proposed in 2014 that researchers could use the blockchain to record pre-specified aspects of their projects, including the study design, analysis plan, and data structure, among others, which could later be verified by consumers of the literature to decrease bias that may be introduced in post-hoc analysis<ref>Slade E, Drysdale H, Goldacre B, COMPare Team. Discrepancies Between Prespecified and Reported Outcomes. Ann Intern Med [Internet]. 2016 Mar 1;164(5):374. Available from: http://www.ncbi.nlm.nih.gov/pubmed/26720309</ref>. The blockchain also offers the potential ability to verify the integrity of actual research data and analysis by outside observers, even if the data themselves are not made publicly available. These types of implementations may lead to improvements in both the integrity of biomedical research as well as bolster public trust in medical research.<br />
<br />
=== Personal Health Records ===<br />
This concept dovetails with the idea of HIE using the blockchain, but focuses more on the secure maintenance of a personal health record (PHR) by patients. No production PHR has been released based on this technology, but concepts such as MedVault <ref>Baxendale G. Can Blockchain Revolutionise EPRs? [Internet]. Vol. 58, ITNOW. 2016. p. 38–9. Available from: http://itnow.oxfordjournals.org/lookup/doi/10.1093/itnow/bww017</ref> use alternative blockchains such as [http://www.Colu.com Colu] to store patient data directly on the blockchain. Others such as [https://devpost.com/software/ehealthwallet eHealthWallet] have also developed prototype PHRs based on the blockchain. Patients could then share or authorize doctors and other health entities to access and modify their data.<br />
<br />
=== Storage of Health Care Data ===<br />
Most of the previous examples use the blockchain not as a direct data storage medium, but instead as a secure reference point for identities, access, and data locations. At least one group from a company called Tierion, which partners with the [http://www.2.forms.healthcare.philips.com/blockchainlabs Philips Blockchain Lab ], has produced a concept called Chainpoint<ref>Vaughan AW, Bukowski J, Wilkinson S, Sporny CM, Shea R, Allen C, et al. Chainpoint: A scalable protocol for anchoring data in the blockchain and generating blockchain receipts [Internet]. 2016. Available from: https://tierion.com/chainpoint</ref>, which proposes to use a [https://proofofexistence.com/about Proof of Existence] concept and Merkle Roots<ref>Merkle RC. PROTOCOLS FOR PUBUC KEY CRYPTOSYSTEMS. In: IEEE Symposium on Security and Privacy [Internet]. 1980. p. 122–34. Available from: http://www.merkle.com/papers/Protocols.pdf</ref> to efficiently store actual patient records on the blockchain without imposing excessive transaction demands on the system.<br />
<br />
=== Billing and Claims Adjudication ===<br />
Blockchain system can help reduce administrative costs and time while automating claims adjudication and payment processing using smart contracts. For example - a smart contract is set up between payer or insurance company, provider, and patient such that when the patient sees a provider, or if a procedure is done, an entry is recorded in the blockchain. Based on the criteria set, the contract can automatically issue reimbursement from the payer as well as co-pay from the patient without having to wait for the insurance approval.<ref>Srinivasan, P. (2017, November 9). Healthcare Blockchain: How Smart Contracts Could Revolutionize Care Delivery. Prolifics. Retrieved from: https://www.prolifics.com/blog/healthcare-blockchain-how-smart-contracts-could-revolutionize-care-delivery</ref><br />
<br />
=== Drug Supply Chain and Prescription Management ===<br />
Counterfeit drugs are a major problem especially in the developing country where it is estimated that about 1 in 10 medical products are counterfeit <ref>WHO. (2017, November 28). 1 in 10 medical products in developing countries is substandard or falsified. Retrieved from: http://www.who.int/en/news-room/detail/28-11-2017-1-in-10-medical-products-in-developing-countries-is-substandard-or-falsified</ref>. Ensuring the integrity of the drug and maintaining a robust audit trail is a must to ensure patient safety. Similarly, this platform can be used in prescription drug management and track history and authenticate prescriptions using smart-contracts. <br />
<br />
=== Few Examples of Current Use Cases and Future Development ===<br />
<br />
* MedRec- it is based on Ethereum platform and focuses on medical data management using smart contracts like managing permissions and authentication processes, data sharing in an interoperable environment between healthcare systems and maintaining an audit log. <ref>Azaria, A., Ekblaw, A., Vieira, T., & Lippman, A. (2016, August 22-24). MedRec: Using Blockchain for Medical Data Access and Permission Management. 2016 2nd International Conference on Open and Big Data (OBD). doi:10.1109/obd.2016.11</ref><br />
<br />
* Guardtime- also focuses on medical data management and has partnered with e-Health authority of Estonia to secure the country's database of health records <ref>Ruubel M. (2016, February 12). Estonian eHealth Authority Partners with Guardtime to Accelerate Transparency and Auditability in Health Care. Retrieved from: https://guardtime.com/blog/estonian-ehealth-partners-guardtime-blockchain-based-transparency</ref>. Also, recently, MyPCR smartphone platform from Guardtime has partnered with Instant Access Medical and Healthcare Gateway in the UK for patient health data management and verification of medication adherence. <ref>Ruubel M. (2018, June 20). World’s first blockchain-supported Personal Care Record Platform launched by Guardtime and partners to up to 30 million NHS patients in the UK. Retrieved from: https://guardtime.com/blog/world-s-first-blockchain-supported-personal-care-record-platform-launched-by-guardtime-and-partners</ref> <br />
<br />
* Blockchain Health- created for healthcare research data management where users can individually authorize the release of their health information to researchers as well as track the use of their data. <ref>BlockchainHealth. (2016). Blockchain for health research. Retrieved from: https://blockchainhealth.co/</ref><br />
<br />
* BlockMedx- it is a startup company which intends to use the blockchain platform to transmit DEA controlled drug prescriptions from physicians to pharmacies and then to patients securely. <ref>BlockMedx. (2018). Retrieved from: https://blockmedx.com/en/</ref><br />
<br />
* MediLedger- another pharmaceutical supply chain management startup company who has partnered with several drug manufacturers and aims to provide an open, secure and interoperable network. <ref>MediLedger. (2018). The MediLedger Project. Retrieved from: https://mediledger.com/</ref><br />
<br />
* Drug and Pharmacy Verification - [https://devpost.com/software/veripharm VeriPharm] has developed a proof of concept that would help track and verify pharmaceuticals from the raw materials to the final product administered to patients.<br />
<br />
* Appointment Scheduling on the Blockchain - [https://devpost.com/software/dhva-appointment-blocks dhva-apointment-blocks]<br />
<br />
* Care Coordination - Projects such as [https://devpost.com/software/simplyvitahlth simplyvitahlth] are geared toward coordinating care between multiple providers and at different institutions to ensure that complex care pathways are being followed appropriately.<br />
<br />
<br />
There are many more potential use-cases for blockchain technology within healthcare, and undoubtedly we will continue to see development in this area in coming years. In 2016, a consortium of sponsors led by [https://gem.co/ Gem] (Whitepaper)<ref>Wood C, Winton B, Carter K, Benkert S, Dodd L, Bradley J, et al. How Blockchain Technology Can Enhance Ehr Operability [Internet]. 2016. Available from: http://research.ark-invest.com/blockchain-and-healthcare</ref> held the first healthcare oriented blockchain conference, [https://godistributed.com/health Distributed: Health] in Nashville, TN. Similarly, the Office of the National Coordinator (ONC) Tech Lab had issued a Blockchain Challenge in July, 2016.<ref>https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab</ref><br />
* The list of submissions and awards can be found [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab here]<br />
<br />
As the healthcare blockchain community grows, gatherings such as these will likely increase and blockchain technologies will increasingly be introduced at major medical conferences.<br />
<br />
== References ==<br />
<references /><br />
<br />
Submitted by Sandeep Regmi<br />
[[Category: BMI512-FALL-18]]<br />
<br />
Submitted by Ben Orwoll<br />
<br />
[[Category: BMI512-FALL-16]]<br />
[[Category: Reviews]]<br />
[[Category: Other Technologies]]</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/The_Blockchain_in_HealthcareThe Blockchain in Healthcare2018-10-19T02:35:04Z<p>Phamnh: /* Cryptocurrency */</p>
<hr />
<div>The blockchain is an idea centered around the concept of a secure, digital ledger system that provides a system for efficient, auditable transactions of almost any type between entities <ref>Tapscott D, Tapscott A. Blockchain Revolution: How the Technology Behind Bitcoin Is Changing Money, Business, and the World. United States: Portfolio; 2016. 1-368 p.</ref>. All information related to blockchain transactions is at once both independently verifiable by all (even outside) parties as correct and also inscrutable to entities without explicit permission. The first and probably most well-known implementation of blockchain technology is [https://bitcoin.org Bitcoin] <ref name="BTC">Nakamoto S. Bitcoin: A Peer-to-Peer Electronic Cash System. WwwBitcoinOrg [Internet]. 2008;9. Available from: https://bitcoin.org/bitcoin.pdf</ref>, but there has been a massive expansion of blockchain use-cases since Bitcoin's initial introduction.<br />
<br />
<br />
<br />
== What is the Blockchain? ==<br />
<br />
First, it should be clear that there is no one blockchain to rule them all. "The Blockchain," as it is often referred, really is a concept of a series (chain) of interrelated sets (blocks) of encrypted information. Hence a chain of blocks, or blockchain. There are many such blockchains in existence, and one could choose to do transactions on any one of them or create a new blockchain.<br />
<br />
<br />
An important aspect of most blockchains is that they are designed to be maintained on a distributed network of multiple nodes. Each node holds a complete copy of the blockchain and adds each sequential new block as it is created. This system allows every transaction on the blockchain to be verified by any or all of the nodes in the network, and also makes it very difficult for the information held in the blockchain to become lost or unavailable if any one or even most of the nodes go offline.<br />
<br />
<br />
Transactions that are set to be added to the blockchain are added to the newest block as soon as it is created. This makes the continued existence of the blockchain dependent on the creation of new blocks. There are several main methods for the creation of new blocks on the network, and the choice of method depends somewhat on the purpose of the blockchain in question. Bitcoin, the first cryptocurrency, uses a method called Proof of Work, but there are at least two methods currently in use:<br />
* [https://en.wikipedia.org/wiki/Proof-of-work_system Proof of Work System (Wikipedia)]<br />
* [https://en.wikipedia.org/wiki/Proof-of-stake Proof of Stake (Wikipedia)] [https://en.bitcoin.it/wiki/Proof_of_Stake Proof of Stake (Bitcoin Wiki)]<br />
<br />
<br />
The blockchain has moved beyond simply processing transactions of cryptocurrency such as Bitcoin. Any data that can be encoded into a cryptographic [https://en.wikipedia.org/wiki/Hash_function hash] can be added to a blockchain. Various different ideas have been proposed, and I will not attempt to list them here, but they are wide ranging.<br />
<br />
<br />
=== Blockchain Development Groups ===<br />
Certainly a non-exhaustive list . . .<br />
<br />
* [https://bitcoin.org/en/ Bitcoin]<br />
<br />
* [https://hyperledger.org The Hyperledger Project]<br />
<br />
* [https://ethereum.org The Ethereum Project]<br />
<br />
* [https://r3cev.com/blog/2016/4/4/introducing-r3-corda-a-distributed-ledger-designed-for-financial-services The CORDA Platform]<br />
<br />
* [http://www.muskokagroup.org/ The Muskoka Group]<br />
<br />
* [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab The ONC Tech Lab]<br />
<br />
== Blockchain Use Cases ==<br />
<br />
=== Cryptocurrency ===<br />
Bitcoin (BTC) was the first cryptocurrency based on the blockchain and was developed by someone calling himself (or herself) Satoshi Nakamoto. The protocol was introduced in 2008 after the publication of a white paper<ref name="BTC" /> describing the algorithm and the mechanisms for generation and distribution of BTC. At this point there are hundreds of cryptocurrencies in circulation according to [http://wikipedia.org Wikipedia], many of which are based on the Bitcoin blockchain, but only a few have gone into widespread use<ref>https://en.wikipedia.org/wiki/List_of_cryptocurrencies</ref>.<br />
<br />
=== Smart Contracts ===<br />
One of the major potential functions of blockchain technology is through the creation of smart contracts. Various components of contracts, including proof of the involved parties, requirements for completion, and actions upon completion of the contract can be encoded in blocks. These can then be added to a blockchain and become available for independent verification, which can even lead to automatic processing of contracts when their requirements have been fulfilled.<br />
<br />
Smart contracts are scripts which have various rules and logic that automatically execute when those rules are met. Smart contracts allow heavily automated workflows between transacting parties in the network while maintaining anonymity. Once the contract has been executed, one can take custody over assets or pre-defined payments can be issued. <ref>Christidis, K & Devetsikiotis, M. (2016, May 10). Blockchains and Smart Contracts for the Internet of Things. IEEE Access, 4, 2292-2303. doi: 10.1109/ACCESS.2016.2566339</ref> They are importantly different in the sense that they are stored on a distributed network and they can be verified as true without knowledge of the contract specifications <ref>https://bitsonblocks.net/2016/02/01/a-gentle-introduction-to-smart-contracts/</ref>.<br />
<br />
[https://ethereum.org The Ethereum Project] was one of the first to introduce the concept of smart contracts using their alternative blockchain and currency token, [https://www.ethereum.org/ether ether].<br />
<br />
=== Securities Exchanges and Finance ===<br />
<br />
One of the hottest arenas for blockchain development currently is in the financial markets, an extension of the original cryptocurrency use cases for the blockchain. Multiple stock markets and other financial firms have initiated investigations and pilot projects into the feasibility and utility of the blockchain for contracts and tracking of financial instruments. NASDAQ has been one of the first major markets to put blockchain technology into use, and has released some information on its implementation, called Linq <ref>http://ir.nasdaq.com/releasedetail.cfm?releaseid=948326</ref><ref>http://www.coindesk.com/hands-on-with-linq-nasdaqs-private-markets-blockchain-project/</ref>. The cryptocurrency website [http://www.coindesk.com Coindesk] has also produced a list of 10 exchanges using or investigating blockchain technologies<ref>http://www.coindesk.com/10-stock-exchanges-blockchain/</ref>.<br />
<br />
<br />
Additionally, financial firms such as Visa have been experimenting with the blockchain for keeping track of transactions as well as with proof of concept applications such as remittance<ref>http://www.coindesk.com/hands-on-with-visa-europes-bitcoin-remittance-app/</ref>.<br />
<br />
== Advantages and Disadvantages of Blockchain ==<br />
<br />
Blockchain is a novel concept and is being explored in various sectors. While there may be several applications and limitations of this technology in future, some of them are highlighted below<ref>Fauvel, W. (2017, August 11). Blockchain Advantage and Disadvantages. Medium. Retrieved from: https://medium.com/nudjed/blockchain-advantage-and-disadvantages-e76dfde3bbc0</ref>:<br />
<br />
=== Pros: ===<br />
# Distributed: There is no single owner of the database. As anyone can contribute and be a part of the network, the risks of data tampering and fraud are minimal. As Nakamoto <ref name="BTC" /> mentioned, as long as the majority of nodes are honest, a random attacker would not be able to alter the history.<br />
# Trustless: As every node in the network will have a copy of the blockchain and they verify the transactions independently. Hence, this system allows transaction even if the parties don't trust each other.<br />
# Immutable: Once the transaction is verified and embedded in the blockchain, it is almost impossible to undo it, and the complexity increases with time as more blocks are added downstream. This allows keeping a track of accurate events that occurred through the history.<br />
# Decentralized: There is no middleman like banks or data owners. This helps avoid manipulation of the market by the owners.<br />
<br />
<br />
=== Cons: ===<br />
# Waste of resources: As several nodes are running and utilizing a huge amount of computing power and electricity to verify and maintain the blockchain, there is more than required redundancy. <br />
# Higher cost for less value: With time, the use of network increases and the complexity of the hashing algorithm also increases. Hence, more resources are required for the same amount of work. This increases the cost of work and transactions gets slower, as miners prioritize the transactions with higher incentives causing a backlog the transactions with smaller values. <br />
# Difficulty to keep up with the size of the block: As the size continues to grow along with the complexity to solve the calculation, new nodes with smaller computing power will have difficulty joining the network and likewise, the older and slower nodes will gradually fade with decreasing incentive for the work. Hence, like Darwin’s theory of the "survival of the fittest", a few larger nodes will dominate the network creating more and more centralization of the system. <br />
# Speculative market: Due to the lack of proper regulation of this system, the market is subject to a great volatility and thus making it risky for investors. <br />
# Immutable smart contracts: As there are clear advantages of having permanent and immutable records, at the same time, there is a bitter flipside to this. For example, if there is a flaw with code that can compromise the system, it is also irreparable and creates the opportunity for the attackers to exploit the same flaw repetitively in future. As time progresses, the capability of repairing the error will be even more complex.<br />
<br />
<br />
<br />
== Potential Use Cases in Healthcare ==<br />
Though there has yet to be a breakthrough report or use-case for blockchain technology in healthcare, there are many potential ways that the blockchain could be implemented within the current healthcare structure. Any list will likely be incomplete, but these examples represent some of the published and available literature on blockchain implementations in health.<br />
<br />
=== Health Information Exchange (HIE) ===<br />
One major area that blockchains may be able to facilitate is the secure access to and communication of patient health records between individuals and institutions. There have been multiple white papers published on the topic, including groups from the Mayo Clinic <ref>Peterson K, Deeduvanu R, Kanjamala P, Boles K. A Blockchain-Based Approach to Health Information Exchange Networks. (1):1–10.</ref> and MIT <ref>Ekblaw A, Azaria A, Halamka JD, Lippman A, Original I, Vieira T. A Case Study for Blockchain in Healthcare: “ MedRec ” prototype for electronic health records and medical research data MedRec: Using Blockchain for Medical Data Access and Permission Management [Internet]. 2016. Available from: https://www.healthit.gov/sites/default/files/5-56-onc_blockchainchallenge_mitwhitepaper.pdf</ref> who described a system for patient information exchange based on blockchain technology that would allow patient-controlled access to records across institutions using HL7 Fast Healthcare Interoperability Resources ([[FHIR]]), [http://json.org JSON], or other encoding system. In these models the actual health care data are not encoded in the blockchain, but are merely references pointing to where the data reside, such as at institutions or in a "data lake" <ref>Linn LA, Koo MB. Blockchain For Health Data and Its Potential Use in Health IT and Health Care Related Research. 2014;1–10.</ref>. Similarly, a group out of China described an app called Healthcare Data Gateway (HGD) that allows patients to view and directly control rule-based access to their health records with a smart phone interface and authentication provided by a blockchain network <ref>Yue X, Wang H, Jin D, Li M, Jiang W. Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst [Internet]. 2016 Oct;40(10):218. Available from: http://dx.doi.org/10.1007/s10916-016-0574-6</ref>. These ideas support the concept of patient-owned medical data, and would have the effect of decentralization of medical records in ways that are as yet undetermined.<br />
<br />
=== Health Research Integrity ===<br />
Academic research is a major driver of advances in health care, but in the setting of limited funding and publication pressures on researchers significant concerns have been raised regarding research integrity<ref>Titus SL, Wells J a, Rhoades LJ. Repairing research integrity. Nature [Internet]. 2008 Jun 19;453(7198):980–2. Available from: http://www.ncbi.nlm.nih.gov/pubmed/18563131</ref>. Organizations such as [http://clinicaltrials.gov ClinicalTrials.gov] and others have been developed to help drive researchers to define endpoints and analysis prior to conducting clinical trials and other studies. As it represents an immutable, verifiable record of events and transactions, the blockchain has been proposed as a potential decentralized resources for helping to ensure biomedical research integrity. Benjamin Carlisle<ref>Carlisle BG. Proof of prespecified endpoints in medical research with the bitcoin blockchain [Internet]. 2014. Available from: http://www.bgcarlisle.com/blog/2014/08/25/proof-of-prespecified-endpoints-in-medical-research-with-the-bitcoin-blockchain/</ref>, followed by several researchers from the UK<ref>Irving G, Holden J. How blockchain-timestamped protocols could improve the trustworthiness of medical science. F1000Research [Internet]. 2016;5:222. Available from: http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4866630/</ref>, proposed in 2014 that researchers could use the blockchain to record pre-specified aspects of their projects, including the study design, analysis plan, and data structure, among others, which could later be verified by consumers of the literature to decrease bias that may be introduced in post-hoc analysis<ref>Slade E, Drysdale H, Goldacre B, COMPare Team. Discrepancies Between Prespecified and Reported Outcomes. Ann Intern Med [Internet]. 2016 Mar 1;164(5):374. Available from: http://www.ncbi.nlm.nih.gov/pubmed/26720309</ref>. The blockchain also offers the potential ability to verify the integrity of actual research data and analysis by outside observers, even if the data themselves are not made publicly available. These types of implementations may lead to improvements in both the integrity of biomedical research as well as bolster public trust in medical research.<br />
<br />
=== Personal Health Records ===<br />
This concept dovetails with the idea of HIE using the blockchain, but focuses more on the secure maintenance of a personal health record (PHR) by patients. No production PHR has been released based on this technology, but concepts such as MedVault <ref>Baxendale G. Can Blockchain Revolutionise EPRs? [Internet]. Vol. 58, ITNOW. 2016. p. 38–9. Available from: http://itnow.oxfordjournals.org/lookup/doi/10.1093/itnow/bww017</ref> use alternative blockchains such as [http://www.Colu.com Colu] to store patient data directly on the blockchain. Others such as [https://devpost.com/software/ehealthwallet eHealthWallet] have also developed prototype PHRs based on the blockchain. Patients could then share or authorize doctors and other health entities to access and modify their data.<br />
<br />
=== Storage of Health Care Data ===<br />
Most of the previous examples use the blockchain not as a direct data storage medium, but instead as a secure reference point for identities, access, and data locations. At least one group from a company called Tierion, which partners with the [http://www.2.forms.healthcare.philips.com/blockchainlabs Philips Blockchain Lab ], has produced a concept called Chainpoint<ref>Vaughan AW, Bukowski J, Wilkinson S, Sporny CM, Shea R, Allen C, et al. Chainpoint: A scalable protocol for anchoring data in the blockchain and generating blockchain receipts [Internet]. 2016. Available from: https://tierion.com/chainpoint</ref>, which proposes to use a [https://proofofexistence.com/about Proof of Existence] concept and Merkle Roots<ref>Merkle RC. PROTOCOLS FOR PUBUC KEY CRYPTOSYSTEMS. In: IEEE Symposium on Security and Privacy [Internet]. 1980. p. 122–34. Available from: http://www.merkle.com/papers/Protocols.pdf</ref> to efficiently store actual patient records on the blockchain without imposing excessive transaction demands on the system.<br />
<br />
=== Billing and Claims Adjudication ===<br />
Blockchain system can help reduce administrative costs and time while automating claims adjudication and payment processing using smart contracts. For example - a smart contract is set up between payer or insurance company, provider, and patient such that when the patient sees a provider, or if a procedure is done, an entry is recorded in the blockchain. Based on the criteria set, the contract can automatically issue reimbursement from the payer as well as co-pay from the patient without having to wait for the insurance approval.<ref>Srinivasan, P. (2017, November 9). Healthcare Blockchain: How Smart Contracts Could Revolutionize Care Delivery. Prolifics. Retrieved from: https://www.prolifics.com/blog/healthcare-blockchain-how-smart-contracts-could-revolutionize-care-delivery</ref><br />
<br />
=== Drug Supply Chain and Prescription Management ===<br />
Counterfeit drugs are a major problem especially in the developing country where it is estimated that about 1 in 10 medical products are counterfeit <ref>WHO. (2017, November 28). 1 in 10 medical products in developing countries is substandard or falsified. Retrieved from: http://www.who.int/en/news-room/detail/28-11-2017-1-in-10-medical-products-in-developing-countries-is-substandard-or-falsified</ref>. Ensuring the integrity of the drug and maintaining a robust audit trail is a must to ensure patient safety. Similarly, this platform can be used in prescription drug management and track history and authenticate prescriptions using smart-contracts. <br />
<br />
=== Few Examples of Current Use Cases and Future Development ===<br />
<br />
* MedRec- it is based on Ethereum platform and focuses on medical data management using smart contracts like managing permissions and authentication processes, data sharing in an interoperable environment between healthcare systems and maintaining an audit log. <ref>Azaria, A., Ekblaw, A., Vieira, T., & Lippman, A. (2016, August 22-24). MedRec: Using Blockchain for Medical Data Access and Permission Management. 2016 2nd International Conference on Open and Big Data (OBD). doi:10.1109/obd.2016.11</ref><br />
<br />
* Guardtime- also focuses on medical data management and has partnered with e-Health authority of Estonia to secure the country's database of health records <ref>Ruubel M. (2016, February 12). Estonian eHealth Authority Partners with Guardtime to Accelerate Transparency and Auditability in Health Care. Retrieved from: https://guardtime.com/blog/estonian-ehealth-partners-guardtime-blockchain-based-transparency</ref>. Also, recently, MyPCR smartphone platform from Guardtime has partnered with Instant Access Medical and Healthcare Gateway in the UK for patient health data management and verification of medication adherence. <ref>Ruubel M. (2018, June 20). World’s first blockchain-supported Personal Care Record Platform launched by Guardtime and partners to up to 30 million NHS patients in the UK. Retrieved from: https://guardtime.com/blog/world-s-first-blockchain-supported-personal-care-record-platform-launched-by-guardtime-and-partners</ref> <br />
<br />
* Blockchain Health- created for healthcare research data management where users can individually authorize the release of their health information to researchers as well as track the use of their data. <ref>BlockchainHealth. (2016). Blockchain for health research. Retrieved from: https://blockchainhealth.co/</ref><br />
<br />
* BlockMedx- it is a startup company which intends to use the blockchain platform to transmit DEA controlled drug prescriptions from physicians to pharmacies and then to patients securely. <ref>BlockMedx. (2018). Retrieved from: https://blockmedx.com/en/</ref><br />
<br />
* MediLedger- another pharmaceutical supply chain management startup company who has partnered with several drug manufacturers and aims to provide an open, secure and interoperable network. <ref>MediLedger. (2018). The MediLedger Project. Retrieved from: https://mediledger.com/</ref><br />
<br />
* Drug and Pharmacy Verification - [https://devpost.com/software/veripharm VeriPharm] has developed a proof of concept that would help track and verify pharmaceuticals from the raw materials to the final product administered to patients.<br />
<br />
* Appointment Scheduling on the Blockchain - [https://devpost.com/software/dhva-appointment-blocks dhva-apointment-blocks]<br />
<br />
* Care Coordination - Projects such as [https://devpost.com/software/simplyvitahlth simplyvitahlth] are geared toward coordinating care between multiple providers and at different institutions to ensure that complex care pathways are being followed appropriately.<br />
<br />
<br />
There are many more potential use-cases for blockchain technology within healthcare, and undoubtedly we will continue to see development in this area in coming years. In 2016, a consortium of sponsors led by [https://gem.co/ Gem] (Whitepaper)<ref>Wood C, Winton B, Carter K, Benkert S, Dodd L, Bradley J, et al. How Blockchain Technology Can Enhance Ehr Operability [Internet]. 2016. Available from: http://research.ark-invest.com/blockchain-and-healthcare</ref> held the first healthcare oriented blockchain conference, [https://godistributed.com/health Distributed: Health] in Nashville, TN. Similarly, the Office of the National Coordinator (ONC) Tech Lab had issued a Blockchain Challenge in July, 2016.<ref>https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab</ref><br />
* The list of submissions and awards can be found [https://oncprojectracking.healthit.gov/wiki/display/TechLabI/Blockchain+Challenge+on+ONC+Tech+Lab here]<br />
<br />
As the healthcare blockchain community grows, gatherings such as these will likely increase and blockchain technologies will increasingly be introduced at major medical conferences.<br />
<br />
== References ==<br />
<references /><br />
<br />
Submitted by Sandeep Regmi<br />
[[Category: BMI512-FALL-18]]<br />
<br />
Submitted by Ben Orwoll<br />
<br />
[[Category: BMI512-FALL-16]]<br />
[[Category: Reviews]]<br />
[[Category: Other Technologies]]</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T02:24:27Z<p>Phamnh: /* Limitations and Proposed Solution */</p>
<hr />
<div>A blockchain is a public distributed ledger that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased or manipulated. <br />
<br />
Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 [5]. Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto[1] as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
'''New Innovations'''<br />
<br />
''Smart Contract''<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain[2], with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
''Proof of Stake''<br />
<br />
There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker. <br />
<br />
''Blockchain Scaling''<br />
<br />
Currently, all computers that participate in mining a blockchain process every transaction. This is very slow and resource wasteful. A solution to this is to calculate how many computers will be needed to validate a new block, and give the task of verifying a transaction to those computers[4]. This will allow parallel processing and speed up transactions. At this point, the details behind how to manage this division of tasks without compromising security still being worked out.<br />
<br />
== Application of Blockchain in Healthcare ==<br />
<br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference [6,7]. <br />
<br />
[https://i.postimg.cc/15PZGyfJ/Figure2.jpg Figure 2. Model for interoperability using blockchain centered around patient controlled medical record]<br />
* In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A).<br />
* As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). <br />
* A blockchain-enabled smart contracts controlled by the patient can be used to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability[6]: <br />
* Digital access rules: The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application<br />
* Data aggregation: Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health<br />
* Data liquidity: Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc.<br />
* Patient identity: Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems<br />
* Data immutability: Since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time.<br />
<br />
== Application of Blockchain in Biomedical Research ==<br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility [8], which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data [9]. A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured [10]. <br />
<br />
Blockchain can be applied to biomedical research in the following ways:<br />
* With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. <br />
* The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated. This will avoid post-hoc data manipulation and posteriori calculus bias. <br />
* Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solutions ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use.<br />
<br />
* The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. Proposed solutions include:<br />
** Validate data using a different approach to consensus such as proof-of-stake[3]. <br />
** Store a summary of, instead of a complete clinical report [6].<br />
** Patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
* A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A few solutions to this problem has been proposed:<br />
** Use permissioned (member-only) blockchain to avoid public exposure.<br />
** Basic demographic information stored on a block chain can also be encrypted to prevent access.<br />
** Store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
* Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. <br />
** Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. <br />
** Patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
* The largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. To overcome this, a few proposals have been made:<br />
** Expand federal incentives to patient-controlled medical record.<br />
** Researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
== References ==<br />
<br />
1. Nakamoto, S. (2008). Bitcoin. A peer-to-peer electronic cash system.<br />
<br />
2. Wood, G. (2014). Ethereum: A secure decentralised generalised transaction ledger. Ethereum project yellow paper, 151, 1-32.<br />
<br />
3. Siim, Janno. "Proof-of-Stake."<br />
<br />
4. Croman, Kyle, et al. "On scaling decentralized blockchains." International Conference on Financial Cryptography and Data Security. Springer, Berlin, Heidelberg, 2016.<br />
<br />
5. Swan, M. (2015). Blockchain: Blueprint for a new economy: " O'Reilly Media, Inc.".<br />
<br />
6. Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230.<br />
<br />
7. Yue, X., Wang, H., Jin, D., Li, M., & Jiang, W. (2016). Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst, 40(10), 218. doi:10.1007/s10916-016-0574-6<br />
<br />
8. Ioannidis, J. P. (2005). Why most published research findings are false. PLoS medicine, 2(8), e124.<br />
<br />
9. Benchoufi, M., & Ravaud, P. (2017). Blockchain technology for improving clinical research quality. Trials, 18(1), 335. doi:10.1186/s13063-017-2035-z<br />
<br />
10. Chu, S. Apple watch release news: survey finds 80 percent of US employees would give health data from wearables to employers. iDigitalTimes (2 February; accessed 2015 07 07).</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T02:18:45Z<p>Phamnh: </p>
<hr />
<div>A blockchain is a public distributed ledger that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased or manipulated. <br />
<br />
Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 [5]. Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto[1] as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
'''New Innovations'''<br />
<br />
''Smart Contract''<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain[2], with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
''Proof of Stake''<br />
<br />
There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker. <br />
<br />
''Blockchain Scaling''<br />
<br />
Currently, all computers that participate in mining a blockchain process every transaction. This is very slow and resource wasteful. A solution to this is to calculate how many computers will be needed to validate a new block, and give the task of verifying a transaction to those computers[4]. This will allow parallel processing and speed up transactions. At this point, the details behind how to manage this division of tasks without compromising security still being worked out.<br />
<br />
== Application of Blockchain in Healthcare ==<br />
<br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference [6,7]. <br />
<br />
[https://i.postimg.cc/15PZGyfJ/Figure2.jpg Figure 2. Model for interoperability using blockchain centered around patient controlled medical record]<br />
* In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A).<br />
* As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). <br />
* A blockchain-enabled smart contracts controlled by the patient can be used to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability[6]: <br />
* Digital access rules: The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application<br />
* Data aggregation: Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health<br />
* Data liquidity: Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc.<br />
* Patient identity: Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems<br />
* Data immutability: Since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time.<br />
<br />
== Application of Blockchain in Biomedical Research ==<br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility [8], which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data [9]. A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured [10]. <br />
<br />
Blockchain can be applied to biomedical research in the following ways:<br />
* With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. <br />
* The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated. This will avoid post-hoc data manipulation and posteriori calculus bias. <br />
* Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use.<br />
<br />
* The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. <br />
** One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake[3]. <br />
** Another proposed solution is to store a summary of, instead of a complete clinical report [6].<br />
** Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Nakamoto, S. (2008). Bitcoin. A peer-to-peer electronic cash system.<br />
<br />
2. Wood, G. (2014). Ethereum: A secure decentralised generalised transaction ledger. Ethereum project yellow paper, 151, 1-32.<br />
<br />
3. Siim, Janno. "Proof-of-Stake."<br />
<br />
4. Croman, Kyle, et al. "On scaling decentralized blockchains." International Conference on Financial Cryptography and Data Security. Springer, Berlin, Heidelberg, 2016.<br />
<br />
5. Swan, M. (2015). Blockchain: Blueprint for a new economy: " O'Reilly Media, Inc.".<br />
<br />
6. Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230.<br />
<br />
7. Yue, X., Wang, H., Jin, D., Li, M., & Jiang, W. (2016). Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst, 40(10), 218. doi:10.1007/s10916-016-0574-6<br />
<br />
8. Ioannidis, J. P. (2005). Why most published research findings are false. PLoS medicine, 2(8), e124.<br />
<br />
9. Benchoufi, M., & Ravaud, P. (2017). Blockchain technology for improving clinical research quality. Trials, 18(1), 335. doi:10.1186/s13063-017-2035-z<br />
<br />
10. Chu, S. Apple watch release news: survey finds 80 percent of US employees would give health data from wearables to employers. iDigitalTimes (2 February; accessed 2015 07 07).</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T02:15:48Z<p>Phamnh: </p>
<hr />
<div>A blockchain is a public distributed ledger that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased or manipulated. <br />
<br />
Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 [5]. Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto[1] as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
'''New Innovations'''<br />
<br />
''Smart Contract''<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain[2], with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
''Proof of Stake''<br />
<br />
There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker. <br />
<br />
''Blockchain Scaling''<br />
<br />
Currently, all computers that participate in mining a blockchain process every transaction. This is very slow and resource wasteful. A solution to this is to calculate how many computers will be needed to validate a new block, and give the task of verifying a transaction to those computers[4]. This will allow parallel processing and speed up transactions. At this point, the details behind how to manage this division of tasks without compromising security still being worked out.<br />
<br />
== Application of Blockchain in Healthcare ==<br />
<br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference [6,7]. <br />
<br />
[https://i.postimg.cc/15PZGyfJ/Figure2.jpg Figure 2. Model for interoperability using blockchain centered around patient controlled medical record]<br />
* In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A).<br />
* As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). <br />
* A blockchain-enabled smart contracts controlled by the patient can be used to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability[6]: <br />
* Digital access rules: The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application<br />
* Data aggregation: Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health<br />
* Data liquidity: Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc.<br />
* Patient identity: Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems<br />
* Data immutability: Since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time.<br />
<br />
== Application of Blockchain in Biomedical Research ==<br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility [8], which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data [9]. A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured [10]. <br />
<br />
Blockchain can be applied to biomedical research in the following ways:<br />
* With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. <br />
* The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated. This will avoid post-hoc data manipulation and posteriori calculus bias. <br />
* Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Nakamoto, S. (2008). Bitcoin. A peer-to-peer electronic cash system.<br />
<br />
2. Wood, G. (2014). Ethereum: A secure decentralised generalised transaction ledger. Ethereum project yellow paper, 151, 1-32.<br />
<br />
3. Siim, Janno. "Proof-of-Stake."<br />
<br />
4. Croman, Kyle, et al. "On scaling decentralized blockchains." International Conference on Financial Cryptography and Data Security. Springer, Berlin, Heidelberg, 2016.<br />
<br />
5. Swan, M. (2015). Blockchain: Blueprint for a new economy: " O'Reilly Media, Inc.".<br />
<br />
6. Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230.<br />
<br />
7. Yue, X., Wang, H., Jin, D., Li, M., & Jiang, W. (2016). Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst, 40(10), 218. doi:10.1007/s10916-016-0574-6<br />
<br />
8. Ioannidis, J. P. (2005). Why most published research findings are false. PLoS medicine, 2(8), e124.<br />
<br />
9. Benchoufi, M., & Ravaud, P. (2017). Blockchain technology for improving clinical research quality. Trials, 18(1), 335. doi:10.1186/s13063-017-2035-z<br />
<br />
10. Chu, S. Apple watch release news: survey finds 80 percent of US employees would give health data from wearables to employers. iDigitalTimes (2 February; accessed 2015 07 07).</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T02:09:30Z<p>Phamnh: </p>
<hr />
<div>A blockchain is a public distributed ledger that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased or manipulated. <br />
<br />
Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 [5]. Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto[1] as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
'''New Innovations'''<br />
<br />
''Smart Contract''<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain[2], with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
''Proof of Stake''<br />
<br />
There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker. <br />
<br />
''Blockchain Scaling''<br />
<br />
Currently, all computers that participate in mining a blockchain process every transaction. This is very slow and resource wasteful. A solution to this is to calculate how many computers will be needed to validate a new block, and give the task of verifying a transaction to those computers[4]. This will allow parallel processing and speed up transactions. At this point, the details behind how to manage this division of tasks without compromising security still being worked out.<br />
<br />
== Application of Blockchain in Healthcare ==<br />
<br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference [6,7]. <br />
<br />
[https://i.postimg.cc/15PZGyfJ/Figure2.jpg Figure 2. Model for interoperability using blockchain centered around patient controlled medical record]<br />
* In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A).<br />
* As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). <br />
* A blockchain-enabled smart contracts controlled by the patient can be used to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability[6]: <br />
* Digital access rules: The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application<br />
* Data aggregation: Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health<br />
* Data liquidity: Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc.<br />
* Patient identity: Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems<br />
* Data immutability: Since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time.<br />
<br />
== Application of Blockchain in Biomedical Research ==<br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Nakamoto, S. (2008). Bitcoin. A peer-to-peer electronic cash system.<br />
<br />
2. Wood, G. (2014). Ethereum: A secure decentralised generalised transaction ledger. Ethereum project yellow paper, 151, 1-32.<br />
<br />
3. Siim, Janno. "Proof-of-Stake."<br />
<br />
4. Croman, Kyle, et al. "On scaling decentralized blockchains." International Conference on Financial Cryptography and Data Security. Springer, Berlin, Heidelberg, 2016.<br />
<br />
5. Swan, M. (2015). Blockchain: Blueprint for a new economy: " O'Reilly Media, Inc.".<br />
<br />
6. Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230.<br />
<br />
7. Yue, X., Wang, H., Jin, D., Li, M., & Jiang, W. (2016). Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst, 40(10), 218. doi:10.1007/s10916-016-0574-6</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T02:07:18Z<p>Phamnh: </p>
<hr />
<div>A blockchain is a public distributed ledger that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased or manipulated. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto[1] as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
'''New Innovations'''<br />
<br />
''Smart Contract''<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain[2], with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
''Proof of Stake''<br />
<br />
There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker. <br />
<br />
''Blockchain Scaling''<br />
<br />
Currently, all computers that participate in mining a blockchain process every transaction. This is very slow and resource wasteful. A solution to this is to calculate how many computers will be needed to validate a new block, and give the task of verifying a transaction to those computers[4]. This will allow parallel processing and speed up transactions. At this point, the details behind how to manage this division of tasks without compromising security still being worked out.<br />
<br />
== Application of Blockchain in Healthcare ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 [5]. Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
<br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference [6,7]. <br />
<br />
[https://i.postimg.cc/15PZGyfJ/Figure2.jpg Figure 2. Model for interoperability using blockchain centered around patient controlled medical record]<br />
* In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A).<br />
* As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). <br />
* A blockchain-enabled smart contracts controlled by the patient can be used to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability[6]: <br />
* Digital access rules: The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application<br />
* Data aggregation: Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health<br />
* Data liquidity: Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc.<br />
* Patient identity: Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems<br />
* Data immutability: Since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time.<br />
<br />
== Application of Blockchain in Biomedical Research ==<br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Nakamoto, S. (2008). Bitcoin. A peer-to-peer electronic cash system.<br />
<br />
2. Wood, G. (2014). Ethereum: A secure decentralised generalised transaction ledger. Ethereum project yellow paper, 151, 1-32.<br />
<br />
3. Siim, Janno. "Proof-of-Stake."<br />
<br />
4. Croman, Kyle, et al. "On scaling decentralized blockchains." International Conference on Financial Cryptography and Data Security. Springer, Berlin, Heidelberg, 2016.<br />
<br />
5. Swan, M. (2015). Blockchain: Blueprint for a new economy: " O'Reilly Media, Inc.".<br />
<br />
6. Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230.<br />
<br />
7. Yue, X., Wang, H., Jin, D., Li, M., & Jiang, W. (2016). Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst, 40(10), 218. doi:10.1007/s10916-016-0574-6</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T02:05:51Z<p>Phamnh: /* Application of Blockchain in Healthcare and Research */</p>
<hr />
<div>A blockchain is a public distributed ledger that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased or manipulated. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto[1] as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
'''New Innovations'''<br />
<br />
''Smart Contract''<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain[2], with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
''Proof of Stake''<br />
<br />
There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker. <br />
<br />
''Blockchain Scaling''<br />
<br />
Currently, all computers that participate in mining a blockchain process every transaction. This is very slow and resource wasteful. A solution to this is to calculate how many computers will be needed to validate a new block, and give the task of verifying a transaction to those computers[4]. This will allow parallel processing and speed up transactions. At this point, the details behind how to manage this division of tasks without compromising security still being worked out.<br />
<br />
== Application of Blockchain in Healthcare ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 [5]. Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
<br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference [6,7]. <br />
<br />
[https://i.postimg.cc/15PZGyfJ/Figure2.jpg Figure 2. Model for interoperability using blockchain centered around patient controlled medical record]<br />
* In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A).<br />
* As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). <br />
* A blockchain-enabled smart contracts controlled by the patient can be used to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability[6]: <br />
* Digital access rules: The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application<br />
* Data aggregation: Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health<br />
* Data liquidity: Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc.<br />
* Patient identity: Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems<br />
* Data immutability: Since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Nakamoto, S. (2008). Bitcoin. A peer-to-peer electronic cash system.<br />
<br />
2. Wood, G. (2014). Ethereum: A secure decentralised generalised transaction ledger. Ethereum project yellow paper, 151, 1-32.<br />
<br />
3. Siim, Janno. "Proof-of-Stake."<br />
<br />
4. Croman, Kyle, et al. "On scaling decentralized blockchains." International Conference on Financial Cryptography and Data Security. Springer, Berlin, Heidelberg, 2016.<br />
<br />
5. Swan, M. (2015). Blockchain: Blueprint for a new economy: " O'Reilly Media, Inc.".<br />
<br />
6. Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230.<br />
<br />
7. Yue, X., Wang, H., Jin, D., Li, M., & Jiang, W. (2016). Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst, 40(10), 218. doi:10.1007/s10916-016-0574-6</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T02:02:42Z<p>Phamnh: /* Application of Blockchain in Healthcare and Research */</p>
<hr />
<div>A blockchain is a public distributed ledger that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased or manipulated. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto[1] as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
'''New Innovations'''<br />
<br />
''Smart Contract''<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain[2], with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
''Proof of Stake''<br />
<br />
There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker. <br />
<br />
''Blockchain Scaling''<br />
<br />
Currently, all computers that participate in mining a blockchain process every transaction. This is very slow and resource wasteful. A solution to this is to calculate how many computers will be needed to validate a new block, and give the task of verifying a transaction to those computers[4]. This will allow parallel processing and speed up transactions. At this point, the details behind how to manage this division of tasks without compromising security still being worked out.<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 [5]. Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
<br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference [6,7]. <br />
<br />
[https://i.postimg.cc/15PZGyfJ/Figure2.jpg Figure 2. Model for interoperability using blockchain centered around patient controlled medical record]<br />
* In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A).<br />
* As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). <br />
* A blockchain-enabled smart contracts controlled by the patient can be used to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability[6]: <br />
* digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Nakamoto, S. (2008). Bitcoin. A peer-to-peer electronic cash system.<br />
<br />
2. Wood, G. (2014). Ethereum: A secure decentralised generalised transaction ledger. Ethereum project yellow paper, 151, 1-32.<br />
<br />
3. Siim, Janno. "Proof-of-Stake."<br />
<br />
4. Croman, Kyle, et al. "On scaling decentralized blockchains." International Conference on Financial Cryptography and Data Security. Springer, Berlin, Heidelberg, 2016.<br />
<br />
5. Swan, M. (2015). Blockchain: Blueprint for a new economy: " O'Reilly Media, Inc.".<br />
<br />
6. Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230.<br />
<br />
7. Yue, X., Wang, H., Jin, D., Li, M., & Jiang, W. (2016). Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst, 40(10), 218. doi:10.1007/s10916-016-0574-6</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T01:58:01Z<p>Phamnh: </p>
<hr />
<div>A blockchain is a public distributed ledger that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased or manipulated. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto[1] as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
'''New Innovations'''<br />
<br />
''Smart Contract''<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain[2], with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
''Proof of Stake''<br />
<br />
There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker. <br />
<br />
''Blockchain Scaling''<br />
<br />
Currently, all computers that participate in mining a blockchain process every transaction. This is very slow and resource wasteful. A solution to this is to calculate how many computers will be needed to validate a new block, and give the task of verifying a transaction to those computers[4]. This will allow parallel processing and speed up transactions. At this point, the details behind how to manage this division of tasks without compromising security still being worked out.<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 [5]. Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
<br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference [6,7]. In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
[https://i.postimg.cc/15PZGyfJ/Figure2.jpg Figure 2. Model for interoperability]<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Nakamoto, S. (2008). Bitcoin. A peer-to-peer electronic cash system.<br />
<br />
2. Wood, G. (2014). Ethereum: A secure decentralised generalised transaction ledger. Ethereum project yellow paper, 151, 1-32.<br />
<br />
3. Siim, Janno. "Proof-of-Stake."<br />
<br />
4. Croman, Kyle, et al. "On scaling decentralized blockchains." International Conference on Financial Cryptography and Data Security. Springer, Berlin, Heidelberg, 2016.<br />
<br />
5. Swan, M. (2015). Blockchain: Blueprint for a new economy: " O'Reilly Media, Inc.".<br />
<br />
6. Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230.<br />
<br />
7. Yue, X., Wang, H., Jin, D., Li, M., & Jiang, W. (2016). Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst, 40(10), 218. doi:10.1007/s10916-016-0574-6</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T01:57:24Z<p>Phamnh: /* Application of Blockchain in Healthcare and Research */</p>
<hr />
<div>A blockchain is a public distributed ledger that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased or manipulated. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto[1] as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
'''New Innovations'''<br />
<br />
''Smart Contract''<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain[2], with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
''Proof of Stake''<br />
<br />
There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker. <br />
<br />
''Blockchain Scaling''<br />
<br />
Currently, all computers that participate in mining a blockchain process every transaction. This is very slow and resource wasteful. A solution to this is to calculate how many computers will be needed to validate a new block, and give the task of verifying a transaction to those computers[4]. This will allow parallel processing and speed up transactions. At this point, the details behind how to manage this division of tasks without compromising security still being worked out.<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 [5]. Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
<br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference [6,7]. In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
[https://i.postimg.cc/15PZGyfJ/Figure2.jpg<br />
== Headline text ==<br />
Figure 2. Model for interoperability]<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Nakamoto, S. (2008). Bitcoin. A peer-to-peer electronic cash system.<br />
<br />
2. Wood, G. (2014). Ethereum: A secure decentralised generalised transaction ledger. Ethereum project yellow paper, 151, 1-32.<br />
<br />
3. Siim, Janno. "Proof-of-Stake."<br />
<br />
4. Croman, Kyle, et al. "On scaling decentralized blockchains." International Conference on Financial Cryptography and Data Security. Springer, Berlin, Heidelberg, 2016.<br />
<br />
5. Swan, M. (2015). Blockchain: Blueprint for a new economy: " O'Reilly Media, Inc.".<br />
<br />
6. Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230.<br />
<br />
7. Yue, X., Wang, H., Jin, D., Li, M., & Jiang, W. (2016). Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst, 40(10), 218. doi:10.1007/s10916-016-0574-6</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T01:55:25Z<p>Phamnh: </p>
<hr />
<div>A blockchain is a public distributed ledger that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased or manipulated. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto[1] as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
'''New Innovations'''<br />
<br />
''Smart Contract''<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain[2], with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
''Proof of Stake''<br />
<br />
There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker. <br />
<br />
''Blockchain Scaling''<br />
<br />
Currently, all computers that participate in mining a blockchain process every transaction. This is very slow and resource wasteful. A solution to this is to calculate how many computers will be needed to validate a new block, and give the task of verifying a transaction to those computers[4]. This will allow parallel processing and speed up transactions. At this point, the details behind how to manage this division of tasks without compromising security still being worked out.<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 [5]. Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
<br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference [6,7]. In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
[https://photos.app.goo.gl/3Np29f5ejDfgZ25R9 Figure 2. Model for interoperability]<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Nakamoto, S. (2008). Bitcoin. A peer-to-peer electronic cash system.<br />
<br />
2. Wood, G. (2014). Ethereum: A secure decentralised generalised transaction ledger. Ethereum project yellow paper, 151, 1-32.<br />
<br />
3. Siim, Janno. "Proof-of-Stake."<br />
<br />
4. Croman, Kyle, et al. "On scaling decentralized blockchains." International Conference on Financial Cryptography and Data Security. Springer, Berlin, Heidelberg, 2016.<br />
<br />
5. Swan, M. (2015). Blockchain: Blueprint for a new economy: " O'Reilly Media, Inc.".<br />
<br />
6. Gordon, W. J., & Catalini, C. (2018). Blockchain Technology for Healthcare: Facilitating the Transition to Patient-Driven Interoperability. Comput Struct Biotechnol J, 16, 224-230.<br />
<br />
7. Yue, X., Wang, H., Jin, D., Li, M., & Jiang, W. (2016). Healthcare Data Gateways: Found Healthcare Intelligence on Blockchain with Novel Privacy Risk Control. J Med Syst, 40(10), 218. doi:10.1007/s10916-016-0574-6</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T01:46:21Z<p>Phamnh: /* References */</p>
<hr />
<div>A blockchain is a public distributed ledger that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased or manipulated. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto[1] as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
'''New Innovations'''<br />
<br />
''Smart Contract''<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain[2], with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
''Proof of Stake''<br />
<br />
There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker. <br />
<br />
''Blockchain Scaling''<br />
<br />
Currently, all computers that participate in mining a blockchain process every transaction. This is very slow and resource wasteful. A solution to this is to calculate how many computers will be needed to validate a new block, and give the task of verifying a transaction to those computers[4]. This will allow parallel processing and speed up transactions. At this point, the details behind how to manage this division of tasks without compromising security still being worked out.<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Nakamoto, S. (2008). Bitcoin. A peer-to-peer electronic cash system.<br />
<br />
2. Wood, G. (2014). Ethereum: A secure decentralised generalised transaction ledger. Ethereum project yellow paper, 151, 1-32.<br />
<br />
3. Siim, Janno. "Proof-of-Stake."<br />
<br />
4. Croman, Kyle, et al. "On scaling decentralized blockchains." International Conference on Financial Cryptography and Data Security. Springer, Berlin, Heidelberg, 2016.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T01:46:05Z<p>Phamnh: /* The Technology Behind Blockchain */</p>
<hr />
<div>A blockchain is a public distributed ledger that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased or manipulated. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto[1] as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
'''New Innovations'''<br />
<br />
''Smart Contract''<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain[2], with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
''Proof of Stake''<br />
<br />
There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker. <br />
<br />
''Blockchain Scaling''<br />
<br />
Currently, all computers that participate in mining a blockchain process every transaction. This is very slow and resource wasteful. A solution to this is to calculate how many computers will be needed to validate a new block, and give the task of verifying a transaction to those computers[4]. This will allow parallel processing and speed up transactions. At this point, the details behind how to manage this division of tasks without compromising security still being worked out.<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Nakamoto, S. (2008). Bitcoin. A peer-to-peer electronic cash system.<br />
<br />
2. Wood, G. (2014). Ethereum: A secure decentralised generalised transaction ledger. Ethereum project yellow paper, 151, 1-32.<br />
<br />
3. Siim, Janno. "Proof-of-Stake."<br />
<br />
4. Gupta, Vinay. “A Brief History of Blockchain.” Harvard Business Review, 5 Apr. 2017, hbr.org/2017/02/a-brief-history-of-blockchain.<br />
<br />
3. Crosby, Michael, et al. "Blockchain technology: Beyond bitcoin." Applied Innovation 2 (2016): 6-10.<br />
<br />
4. Marr, Bernard. “A Very Brief History Of Blockchain Technology Everyone Should Read.” Forbes, Forbes Magazine, 20 Mar. 2018, www.forbes.com/sites/bernardmarr/2018/02/16/a-very-brief-history-of-blockchain-technology-everyone-should-read/#5bde14d57bc4.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T01:43:56Z<p>Phamnh: /* The Technology Behind Blockchain */</p>
<hr />
<div>A blockchain is a public distributed ledger that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased or manipulated. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto[1] as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
'''New Innovations'''<br />
<br />
''Smart Contract''<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain[2], with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
''Proof of Stake''<br />
<br />
There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker. <br />
<br />
''Blockchain Scaling''<br />
<br />
Currently, all computers that participate in mining a blockchain process every transaction. This is very slow and resource wasteful. A solution to this is to calculate how many computers will be needed to validate a new block, and give the task of verifying a transaction to those computers. This will allow parallel processing and speed up transactions. At this point, the details behind how to manage this division of tasks without compromising security still being worked out.<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Nakamoto, S. (2008). Bitcoin. A peer-to-peer electronic cash system.<br />
<br />
2. Wood, G. (2014). Ethereum: A secure decentralised generalised transaction ledger. Ethereum project yellow paper, 151, 1-32.<br />
<br />
3. Siim, Janno. "Proof-of-Stake."<br />
<br />
4. Gupta, Vinay. “A Brief History of Blockchain.” Harvard Business Review, 5 Apr. 2017, hbr.org/2017/02/a-brief-history-of-blockchain.<br />
<br />
3. Crosby, Michael, et al. "Blockchain technology: Beyond bitcoin." Applied Innovation 2 (2016): 6-10.<br />
<br />
4. Marr, Bernard. “A Very Brief History Of Blockchain Technology Everyone Should Read.” Forbes, Forbes Magazine, 20 Mar. 2018, www.forbes.com/sites/bernardmarr/2018/02/16/a-very-brief-history-of-blockchain-technology-everyone-should-read/#5bde14d57bc4.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T01:38:02Z<p>Phamnh: /* References */</p>
<hr />
<div>A blockchain is a public distributed ledger that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased or manipulated. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto[1] as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
'''New Innovations'''<br />
<br />
''Smart Contract''<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain[2], with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
''Proof of Stake''<br />
<br />
There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker. <br />
<br />
''Blockchain Scaling''<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Nakamoto, S. (2008). Bitcoin. A peer-to-peer electronic cash system.<br />
<br />
2. Wood, G. (2014). Ethereum: A secure decentralised generalised transaction ledger. Ethereum project yellow paper, 151, 1-32.<br />
<br />
3. Siim, Janno. "Proof-of-Stake."<br />
<br />
4. Gupta, Vinay. “A Brief History of Blockchain.” Harvard Business Review, 5 Apr. 2017, hbr.org/2017/02/a-brief-history-of-blockchain.<br />
<br />
3. Crosby, Michael, et al. "Blockchain technology: Beyond bitcoin." Applied Innovation 2 (2016): 6-10.<br />
<br />
4. Marr, Bernard. “A Very Brief History Of Blockchain Technology Everyone Should Read.” Forbes, Forbes Magazine, 20 Mar. 2018, www.forbes.com/sites/bernardmarr/2018/02/16/a-very-brief-history-of-blockchain-technology-everyone-should-read/#5bde14d57bc4.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T01:35:27Z<p>Phamnh: /* The Technology Behind Blockchain */</p>
<hr />
<div>A blockchain is a public distributed ledger that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased or manipulated. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto[1] as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
'''New Innovations'''<br />
<br />
''Smart Contract''<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain[2], with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
''Proof of Stake''<br />
<br />
There are some issues with the original Proof of Work that Satoshi created: 1) it was very resource intensive and 2) as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker. <br />
<br />
''Blockchain Scaling''<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Nakamoto, S. (2008). Bitcoin. A peer-to-peer electronic cash system.<br />
<br />
2. Wood, G. (2014). Ethereum: A secure decentralised generalised transaction ledger. Ethereum project yellow paper, 151, 1-32.<br />
<br />
3. <br />
<br />
2. Gupta, Vinay. “A Brief History of Blockchain.” Harvard Business Review, 5 Apr. 2017, hbr.org/2017/02/a-brief-history-of-blockchain.<br />
<br />
3. Crosby, Michael, et al. "Blockchain technology: Beyond bitcoin." Applied Innovation 2 (2016): 6-10.<br />
<br />
4. Marr, Bernard. “A Very Brief History Of Blockchain Technology Everyone Should Read.” Forbes, Forbes Magazine, 20 Mar. 2018, www.forbes.com/sites/bernardmarr/2018/02/16/a-very-brief-history-of-blockchain-technology-everyone-should-read/#5bde14d57bc4.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T01:34:09Z<p>Phamnh: /* The Technology Behind Blockchain */</p>
<hr />
<div>A blockchain is a public distributed ledger that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased or manipulated. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto[1] as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
'''New Innovations'''<br />
<br />
''Smart Contract''<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain[2], with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
''Proof of Stake''<br />
<br />
There are some issues with the original Proof of Work that Satoshi created was that it was very resource intensive, and as the bitcoin reward becomes harder to obtain as the blockchain grows, there is less incentive to mine. With fewer miners come fewer validators of the block which could allow malicious actors to introduce fake block into the chain. An alternative to Proof of Work is Proof of Stake. In Proof of Stake, the amount of work a user can do depends on their "wealth," or the amount of currency they own (if they own 1% of the currency, they can mine 1% of the block). In order for someone to manipulate the block, they have to own more than a majority of the currency (51% or more), making successful attacks on the blockchain very expensive. Furthermore, the attack would devalue the currency, resulting in a big hit to the attacker. <br />
<br />
''Blockchain Scaling''<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Nakamoto, S. (2008). Bitcoin. A peer-to-peer electronic cash system.<br />
<br />
2. Wood, G. (2014). Ethereum: A secure decentralised generalised transaction ledger. Ethereum project yellow paper, 151, 1-32.<br />
<br />
3. <br />
<br />
2. Gupta, Vinay. “A Brief History of Blockchain.” Harvard Business Review, 5 Apr. 2017, hbr.org/2017/02/a-brief-history-of-blockchain.<br />
<br />
3. Crosby, Michael, et al. "Blockchain technology: Beyond bitcoin." Applied Innovation 2 (2016): 6-10.<br />
<br />
4. Marr, Bernard. “A Very Brief History Of Blockchain Technology Everyone Should Read.” Forbes, Forbes Magazine, 20 Mar. 2018, www.forbes.com/sites/bernardmarr/2018/02/16/a-very-brief-history-of-blockchain-technology-everyone-should-read/#5bde14d57bc4.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T00:48:32Z<p>Phamnh: </p>
<hr />
<div>A blockchain is a public distributed ledger that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased or manipulated. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto[1] as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
'''New Innovations'''<br />
<br />
''Smart Contract''<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain[2], with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
''Proof of Stake''<br />
<br />
<br />
<br />
''Blockchain Scaling''<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Nakamoto, S. (2008). Bitcoin. A peer-to-peer electronic cash system.<br />
<br />
2. Wood, G. (2014). Ethereum: A secure decentralised generalised transaction ledger. Ethereum project yellow paper, 151, 1-32.<br />
<br />
3. <br />
<br />
2. Gupta, Vinay. “A Brief History of Blockchain.” Harvard Business Review, 5 Apr. 2017, hbr.org/2017/02/a-brief-history-of-blockchain.<br />
<br />
3. Crosby, Michael, et al. "Blockchain technology: Beyond bitcoin." Applied Innovation 2 (2016): 6-10.<br />
<br />
4. Marr, Bernard. “A Very Brief History Of Blockchain Technology Everyone Should Read.” Forbes, Forbes Magazine, 20 Mar. 2018, www.forbes.com/sites/bernardmarr/2018/02/16/a-very-brief-history-of-blockchain-technology-everyone-should-read/#5bde14d57bc4.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T00:39:38Z<p>Phamnh: /* References */</p>
<hr />
<div>A blockchain is a public distributed ledger that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased or manipulated. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== History of Blockchain ==<br />
<br />
<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto[1] as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
'''New Innovations'''<br />
<br />
''Smart Contract''<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain[2], with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
''Proof of Stake''<br />
<br />
<br />
<br />
''Blockchain Scaling''<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Nakamoto, S. (2008). Bitcoin. A peer-to-peer electronic cash system.<br />
<br />
2. Wood, G. (2014). Ethereum: A secure decentralised generalised transaction ledger. Ethereum project yellow paper, 151, 1-32.<br />
<br />
3. <br />
<br />
2. Gupta, Vinay. “A Brief History of Blockchain.” Harvard Business Review, 5 Apr. 2017, hbr.org/2017/02/a-brief-history-of-blockchain.<br />
<br />
3. Crosby, Michael, et al. "Blockchain technology: Beyond bitcoin." Applied Innovation 2 (2016): 6-10.<br />
<br />
4. Marr, Bernard. “A Very Brief History Of Blockchain Technology Everyone Should Read.” Forbes, Forbes Magazine, 20 Mar. 2018, www.forbes.com/sites/bernardmarr/2018/02/16/a-very-brief-history-of-blockchain-technology-everyone-should-read/#5bde14d57bc4.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T00:36:32Z<p>Phamnh: </p>
<hr />
<div>A blockchain is a public distributed ledger that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased or manipulated. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== History of Blockchain ==<br />
<br />
<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto[1] as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
'''New Innovations'''<br />
<br />
''Smart Contract''<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain[2], with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
''Proof of Stake''<br />
<br />
<br />
<br />
''Blockchain Scaling''<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Nakamoto, S. (2008). Bitcoin. A peer-to-peer electronic cash system. Siim, J. Proof-of-Stake.<br />
<br />
2. Wood, G. (2014). Ethereum: A secure decentralised generalised transaction ledger. Ethereum project yellow paper, 151, 1-32.<br />
<br />
2. Gupta, Vinay. “A Brief History of Blockchain.” Harvard Business Review, 5 Apr. 2017, hbr.org/2017/02/a-brief-history-of-blockchain.<br />
<br />
3. Crosby, Michael, et al. "Blockchain technology: Beyond bitcoin." Applied Innovation 2 (2016): 6-10.<br />
<br />
4. Marr, Bernard. “A Very Brief History Of Blockchain Technology Everyone Should Read.” Forbes, Forbes Magazine, 20 Mar. 2018, www.forbes.com/sites/bernardmarr/2018/02/16/a-very-brief-history-of-blockchain-technology-everyone-should-read/#5bde14d57bc4.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T00:35:56Z<p>Phamnh: </p>
<hr />
<div>A blockchain is a public distributed ledger that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== History of Blockchain ==<br />
<br />
<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto[1] as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
'''New Innovations'''<br />
<br />
''Smart Contract''<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain[2], with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
''Proof of Stake''<br />
<br />
<br />
<br />
''Blockchain Scaling''<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Nakamoto, S. (2008). Bitcoin. A peer-to-peer electronic cash system. Siim, J. Proof-of-Stake.<br />
<br />
2. Wood, G. (2014). Ethereum: A secure decentralised generalised transaction ledger. Ethereum project yellow paper, 151, 1-32.<br />
<br />
2. Gupta, Vinay. “A Brief History of Blockchain.” Harvard Business Review, 5 Apr. 2017, hbr.org/2017/02/a-brief-history-of-blockchain.<br />
<br />
3. Crosby, Michael, et al. "Blockchain technology: Beyond bitcoin." Applied Innovation 2 (2016): 6-10.<br />
<br />
4. Marr, Bernard. “A Very Brief History Of Blockchain Technology Everyone Should Read.” Forbes, Forbes Magazine, 20 Mar. 2018, www.forbes.com/sites/bernardmarr/2018/02/16/a-very-brief-history-of-blockchain-technology-everyone-should-read/#5bde14d57bc4.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T00:35:05Z<p>Phamnh: /* The Technology Behind Blockchain */</p>
<hr />
<div>A blockchain is a public distributed ledgers that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== History of Blockchain ==<br />
<br />
<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto[1] as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
'''New Innovations'''<br />
<br />
''Smart Contract''<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain[2], with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
''Proof of Stake''<br />
<br />
<br />
<br />
''Blockchain Scaling''<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Nakamoto, S. (2008). Bitcoin. A peer-to-peer electronic cash system. Siim, J. Proof-of-Stake.<br />
<br />
2. Wood, G. (2014). Ethereum: A secure decentralised generalised transaction ledger. Ethereum project yellow paper, 151, 1-32.<br />
<br />
2. Gupta, Vinay. “A Brief History of Blockchain.” Harvard Business Review, 5 Apr. 2017, hbr.org/2017/02/a-brief-history-of-blockchain.<br />
<br />
3. Crosby, Michael, et al. "Blockchain technology: Beyond bitcoin." Applied Innovation 2 (2016): 6-10.<br />
<br />
4. Marr, Bernard. “A Very Brief History Of Blockchain Technology Everyone Should Read.” Forbes, Forbes Magazine, 20 Mar. 2018, www.forbes.com/sites/bernardmarr/2018/02/16/a-very-brief-history-of-blockchain-technology-everyone-should-read/#5bde14d57bc4.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T00:32:17Z<p>Phamnh: /* References */</p>
<hr />
<div>A blockchain is a public distributed ledgers that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== History of Blockchain ==<br />
<br />
<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto[1] as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction[2]. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
'''New Innovations'''<br />
<br />
''Smart Contract''<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain (Wood, 2014), with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
''Proof of Stake''<br />
<br />
<br />
<br />
''Blockchain Scaling''<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Nakamoto, S. (2008). Bitcoin. A peer-to-peer electronic cash system. Siim, J. Proof-of-Stake.<br />
<br />
2. Wood, G. (2014). Ethereum: A secure decentralised generalised transaction ledger. Ethereum project yellow paper, 151, 1-32.<br />
<br />
2. Gupta, Vinay. “A Brief History of Blockchain.” Harvard Business Review, 5 Apr. 2017, hbr.org/2017/02/a-brief-history-of-blockchain.<br />
<br />
3. Crosby, Michael, et al. "Blockchain technology: Beyond bitcoin." Applied Innovation 2 (2016): 6-10.<br />
<br />
4. Marr, Bernard. “A Very Brief History Of Blockchain Technology Everyone Should Read.” Forbes, Forbes Magazine, 20 Mar. 2018, www.forbes.com/sites/bernardmarr/2018/02/16/a-very-brief-history-of-blockchain-technology-everyone-should-read/#5bde14d57bc4.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T00:31:06Z<p>Phamnh: /* The Technology Behind Blockchain */</p>
<hr />
<div>A blockchain is a public distributed ledgers that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== History of Blockchain ==<br />
<br />
<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto[1] as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction[2]. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
'''New Innovations'''<br />
<br />
''Smart Contract''<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain (Wood, 2014), with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
''Proof of Stake''<br />
<br />
<br />
<br />
''Blockchain Scaling''<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Nakamoto, S. (2008). Bitcoin. A peer-to-peer electronic cash system. Siim, J. Proof-of-Stake.<br />
<br />
2. Gupta, Vinay. “A Brief History of Blockchain.” Harvard Business Review, 5 Apr. 2017, hbr.org/2017/02/a-brief-history-of-blockchain.<br />
<br />
3. Crosby, Michael, et al. "Blockchain technology: Beyond bitcoin." Applied Innovation 2 (2016): 6-10.<br />
<br />
4. Marr, Bernard. “A Very Brief History Of Blockchain Technology Everyone Should Read.” Forbes, Forbes Magazine, 20 Mar. 2018, www.forbes.com/sites/bernardmarr/2018/02/16/a-very-brief-history-of-blockchain-technology-everyone-should-read/#5bde14d57bc4.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T00:29:17Z<p>Phamnh: /* The Technology Behind Blockchain */</p>
<hr />
<div>A blockchain is a public distributed ledgers that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== History of Blockchain ==<br />
<br />
<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto[1] as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction[2]. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
'''New Innovations'''<br />
<br />
Smart contract<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain (Wood, 2014), with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
Proof of Stake<br />
<br />
<br />
<br />
Blockchain scaling<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Nakamoto, S. (2008). Bitcoin. A peer-to-peer electronic cash system. Siim, J. Proof-of-Stake.<br />
<br />
2. Gupta, Vinay. “A Brief History of Blockchain.” Harvard Business Review, 5 Apr. 2017, hbr.org/2017/02/a-brief-history-of-blockchain.<br />
<br />
3. Crosby, Michael, et al. "Blockchain technology: Beyond bitcoin." Applied Innovation 2 (2016): 6-10.<br />
<br />
4. Marr, Bernard. “A Very Brief History Of Blockchain Technology Everyone Should Read.” Forbes, Forbes Magazine, 20 Mar. 2018, www.forbes.com/sites/bernardmarr/2018/02/16/a-very-brief-history-of-blockchain-technology-everyone-should-read/#5bde14d57bc4.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T00:24:35Z<p>Phamnh: /* References */</p>
<hr />
<div>A blockchain is a public distributed ledgers that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== History of Blockchain ==<br />
<br />
<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto (Nakamoto, 2008)as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction[2]. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain (Wood, 2014), with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
'''New Innovations'''<br />
<br />
Smart contract<br />
<br />
Proof of Stake<br />
<br />
Blockchain scaling<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Nakamoto, S. (2008). Bitcoin. A peer-to-peer electronic cash system. Siim, J. Proof-of-Stake.<br />
<br />
2. Gupta, Vinay. “A Brief History of Blockchain.” Harvard Business Review, 5 Apr. 2017, hbr.org/2017/02/a-brief-history-of-blockchain.<br />
<br />
3. Crosby, Michael, et al. "Blockchain technology: Beyond bitcoin." Applied Innovation 2 (2016): 6-10.<br />
<br />
4. Marr, Bernard. “A Very Brief History Of Blockchain Technology Everyone Should Read.” Forbes, Forbes Magazine, 20 Mar. 2018, www.forbes.com/sites/bernardmarr/2018/02/16/a-very-brief-history-of-blockchain-technology-everyone-should-read/#5bde14d57bc4.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T00:20:58Z<p>Phamnh: /* The Technology Behind Blockchain */</p>
<hr />
<div>A blockchain is a public distributed ledgers that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== History of Blockchain ==<br />
<br />
<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto (Nakamoto, 2008)as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction[2]. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
The technology of Bitcoin and blockchain has several advantages:<br />
* The public key is cryptographically generated, allowing for a degree of anonymity (if an individual can be linked to a public key, however, the transaction is no longer anonymous)<br />
* Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier.<br />
* Since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain (Wood, 2014), with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
'''New Innovations'''<br />
<br />
Smart contract<br />
<br />
Proof of Stake<br />
<br />
Blockchain scaling<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Gupta, Vinay. “A Brief History of Blockchain.” Harvard Business Review, 5 Apr. 2017, hbr.org/2017/02/a-brief-history-of-blockchain.<br />
<br />
2. Crosby, Michael, et al. "Blockchain technology: Beyond bitcoin." Applied Innovation 2 (2016): 6-10.<br />
<br />
3. Marr, Bernard. “A Very Brief History Of Blockchain Technology Everyone Should Read.” Forbes, Forbes Magazine, 20 Mar. 2018, www.forbes.com/sites/bernardmarr/2018/02/16/a-very-brief-history-of-blockchain-technology-everyone-should-read/#5bde14d57bc4.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T00:18:02Z<p>Phamnh: /* The Technology Behind Blockchain */</p>
<hr />
<div>A blockchain is a public distributed ledgers that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== History of Blockchain ==<br />
<br />
<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto (Nakamoto, 2008)as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction[2]. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
* Each user of Bitcoin is given a “public key” and a “private key.” <br />
* When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
* This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
* The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
* To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
* The miner node is compensated for their work by a small amount of Bitcoin. <br />
* The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
* This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
* All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
<br />
The technology of Bitcoin and blockchain has several advantages. The public key is cryptographically generated, allowing for anonymity. Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier. Furthermore, since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain (Wood, 2014), with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
'''New Innovations'''<br />
<br />
Smart contract<br />
<br />
Proof of Stake<br />
<br />
Blockchain scaling<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Gupta, Vinay. “A Brief History of Blockchain.” Harvard Business Review, 5 Apr. 2017, hbr.org/2017/02/a-brief-history-of-blockchain.<br />
<br />
2. Crosby, Michael, et al. "Blockchain technology: Beyond bitcoin." Applied Innovation 2 (2016): 6-10.<br />
<br />
3. Marr, Bernard. “A Very Brief History Of Blockchain Technology Everyone Should Read.” Forbes, Forbes Magazine, 20 Mar. 2018, www.forbes.com/sites/bernardmarr/2018/02/16/a-very-brief-history-of-blockchain-technology-everyone-should-read/#5bde14d57bc4.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-19T00:16:31Z<p>Phamnh: </p>
<hr />
<div>A blockchain is a public distributed ledgers that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== History of Blockchain ==<br />
<br />
<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Blockchain was first introduced in 2008 by Satoshi Nakamoto (Nakamoto, 2008)as the underlying technology behind bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction[2]. The algorithm for how bitcoin works were explained by Nakamoto as followed:<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
Each user of Bitcoin is given a “public key” and a “private key.” <br />
When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. <br />
This transaction is broadcasted to the entire network, and is verified by every node in the network (called “miner” node). <br />
The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. <br />
To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. <br />
The miner node is compensated for their work by a small amount of Bitcoin. <br />
The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. <br />
This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” <br />
All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
<br />
The technology of Bitcoin and blockchain has several advantages. The public key is cryptographically generated, allowing for anonymity. Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier. Furthermore, since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain (Wood, 2014), with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
'''New Innovations'''<br />
<br />
Smart contract<br />
<br />
Proof of Stake<br />
<br />
Blockchain scaling<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Gupta, Vinay. “A Brief History of Blockchain.” Harvard Business Review, 5 Apr. 2017, hbr.org/2017/02/a-brief-history-of-blockchain.<br />
<br />
2. Crosby, Michael, et al. "Blockchain technology: Beyond bitcoin." Applied Innovation 2 (2016): 6-10.<br />
<br />
3. Marr, Bernard. “A Very Brief History Of Blockchain Technology Everyone Should Read.” Forbes, Forbes Magazine, 20 Mar. 2018, www.forbes.com/sites/bernardmarr/2018/02/16/a-very-brief-history-of-blockchain-technology-everyone-should-read/#5bde14d57bc4.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-17T05:49:19Z<p>Phamnh: /* References */</p>
<hr />
<div>A blockchain is a public distributed ledgers that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== History of Blockchain ==<br />
<br />
<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Since its introduction in 2008 by Satoshi Nakamoto (Nakamoto, 2008), blockchain has been receiving a lot of attention due to its application in cryptocurrency. The most popular example of blockchain technology is Bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction (Crosby, Pattanayak, Verma, & Kalyanaraman, 2016). Each user of Bitcoin is given a “public key” and a “private key.” When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. This transaction is broadcasted to the entire network (Figure 1), and is verified by every node in the network (called “miner” node). The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. The miner node is compensated for their work by a small amount of Bitcoin. The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
The technology of Bitcoin and blockchain has several advantages. The public key is cryptographically generated, allowing for anonymity. Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier. Furthermore, since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain (Wood, 2014), with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
'''New Innovations'''<br />
<br />
Smart contract<br />
<br />
Proof of Stake<br />
<br />
Blockchain scaling<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Gupta, Vinay. “A Brief History of Blockchain.” Harvard Business Review, 5 Apr. 2017, hbr.org/2017/02/a-brief-history-of-blockchain.<br />
<br />
2. Crosby, Michael, et al. "Blockchain technology: Beyond bitcoin." Applied Innovation 2 (2016): 6-10.<br />
<br />
3. Marr, Bernard. “A Very Brief History Of Blockchain Technology Everyone Should Read.” Forbes, Forbes Magazine, 20 Mar. 2018, www.forbes.com/sites/bernardmarr/2018/02/16/a-very-brief-history-of-blockchain-technology-everyone-should-read/#5bde14d57bc4.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-17T05:44:04Z<p>Phamnh: /* References */</p>
<hr />
<div>A blockchain is a public distributed ledgers that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== History of Blockchain ==<br />
<br />
<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Since its introduction in 2008 by Satoshi Nakamoto (Nakamoto, 2008), blockchain has been receiving a lot of attention due to its application in cryptocurrency. The most popular example of blockchain technology is Bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction (Crosby, Pattanayak, Verma, & Kalyanaraman, 2016). Each user of Bitcoin is given a “public key” and a “private key.” When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. This transaction is broadcasted to the entire network (Figure 1), and is verified by every node in the network (called “miner” node). The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. The miner node is compensated for their work by a small amount of Bitcoin. The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
The technology of Bitcoin and blockchain has several advantages. The public key is cryptographically generated, allowing for anonymity. Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier. Furthermore, since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain (Wood, 2014), with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
'''New Innovations'''<br />
<br />
Smart contract<br />
<br />
Proof of Stake<br />
<br />
Blockchain scaling<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Gupta, Vinay. “A Brief History of Blockchain.” Harvard Business Review, 5 Apr. 2017, hbr.org/2017/02/a-brief-history-of-blockchain.<br />
<br />
2. Crosby, Michael, et al. "Blockchain technology: Beyond bitcoin." Applied Innovation 2 (2016): 6-10.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-17T05:42:33Z<p>Phamnh: </p>
<hr />
<div>A blockchain is a public distributed ledgers that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== History of Blockchain ==<br />
<br />
<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Since its introduction in 2008 by Satoshi Nakamoto (Nakamoto, 2008), blockchain has been receiving a lot of attention due to its application in cryptocurrency. The most popular example of blockchain technology is Bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction (Crosby, Pattanayak, Verma, & Kalyanaraman, 2016). Each user of Bitcoin is given a “public key” and a “private key.” When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. This transaction is broadcasted to the entire network (Figure 1), and is verified by every node in the network (called “miner” node). The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. The miner node is compensated for their work by a small amount of Bitcoin. The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
The technology of Bitcoin and blockchain has several advantages. The public key is cryptographically generated, allowing for anonymity. Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier. Furthermore, since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain (Wood, 2014), with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
'''New Innovations'''<br />
<br />
Smart contract<br />
<br />
Proof of Stake<br />
<br />
Blockchain scaling<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.<br />
<br />
<br />
== References ==<br />
<br />
1. Gupta, Vinay. “A Brief History of Blockchain.” Harvard Business Review, 5 Apr. 2017, hbr.org/2017/02/a-brief-history-of-blockchain.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-17T05:35:50Z<p>Phamnh: /* The Technology Behind Blockchain */</p>
<hr />
<div>A blockchain is a public distributed ledgers that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== History of Blockchain ==<br />
<br />
<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Since its introduction in 2008 by Satoshi Nakamoto (Nakamoto, 2008), blockchain has been receiving a lot of attention due to its application in cryptocurrency. The most popular example of blockchain technology is Bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction (Crosby, Pattanayak, Verma, & Kalyanaraman, 2016). Each user of Bitcoin is given a “public key” and a “private key.” When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. This transaction is broadcasted to the entire network (Figure 1), and is verified by every node in the network (called “miner” node). The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. The miner node is compensated for their work by a small amount of Bitcoin. The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
The technology of Bitcoin and blockchain has several advantages. The public key is cryptographically generated, allowing for anonymity. Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier. Furthermore, since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain (Wood, 2014), with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
'''New Innovations'''<br />
<br />
Smart contract<br />
<br />
Proof of Stake<br />
<br />
Blockchain scaling<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-17T05:34:28Z<p>Phamnh: /* The Technology Behind Blockchain */</p>
<hr />
<div>A blockchain is a public distributed ledgers that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== History of Blockchain ==<br />
<br />
<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Since its introduction in 2008 by Satoshi Nakamoto (Nakamoto, 2008), blockchain has been receiving a lot of attention due to its application in cryptocurrency. The most popular example of blockchain technology is Bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction (Crosby, Pattanayak, Verma, & Kalyanaraman, 2016). Each user of Bitcoin is given a “public key” and a “private key.” When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. This transaction is broadcasted to the entire network (Figure 1), and is verified by every node in the network (called “miner” node). The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. The miner node is compensated for their work by a small amount of Bitcoin. The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
The technology of Bitcoin and blockchain has several advantages. The public key is cryptographically generated, allowing for anonymity. Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier. Furthermore, since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain (Wood, 2014), with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
'''New Innovations'''<br />
<br />
Smart contract<br />
<br />
Proof of Stake<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-17T05:33:33Z<p>Phamnh: /* The Technology Behind Blockchain */</p>
<hr />
<div>A blockchain is a public distributed ledgers that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== History of Blockchain ==<br />
<br />
<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
<br />
Since its introduction in 2008 by Satoshi Nakamoto (Nakamoto, 2008), blockchain has been receiving a lot of attention due to its application in cryptocurrency. The most popular example of blockchain technology is Bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction (Crosby, Pattanayak, Verma, & Kalyanaraman, 2016). Each user of Bitcoin is given a “public key” and a “private key.” When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. This transaction is broadcasted to the entire network (Figure 1), and is verified by every node in the network (called “miner” node). The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. The miner node is compensated for their work by a small amount of Bitcoin. The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
The technology of Bitcoin and blockchain has several advantages. The public key is cryptographically generated, allowing for anonymity. Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier. Furthermore, since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain (Wood, 2014), with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
'''New Innovations'''<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-17T05:33:19Z<p>Phamnh: /* The Technology Behind Blockchain */</p>
<hr />
<div>A blockchain is a public distributed ledgers that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== History of Blockchain ==<br />
<br />
<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
'''Bitcoin'''<br />
Since its introduction in 2008 by Satoshi Nakamoto (Nakamoto, 2008), blockchain has been receiving a lot of attention due to its application in cryptocurrency. The most popular example of blockchain technology is Bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction (Crosby, Pattanayak, Verma, & Kalyanaraman, 2016). Each user of Bitcoin is given a “public key” and a “private key.” When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. This transaction is broadcasted to the entire network (Figure 1), and is verified by every node in the network (called “miner” node). The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. The miner node is compensated for their work by a small amount of Bitcoin. The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
The technology of Bitcoin and blockchain has several advantages. The public key is cryptographically generated, allowing for anonymity. Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier. Furthermore, since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain (Wood, 2014), with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
'''New Innovations'''<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-17T05:27:55Z<p>Phamnh: </p>
<hr />
<div>A blockchain is a public distributed ledgers that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple whitepapers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== History of Blockchain ==<br />
<br />
<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
Since its introduction in 2008 by Satoshi Nakamoto (Nakamoto, 2008), blockchain has been receiving a lot of attention due to its application in cryptocurrency. The most popular example of blockchain technology is Bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction (Crosby, Pattanayak, Verma, & Kalyanaraman, 2016). Each user of Bitcoin is given a “public key” and a “private key.” When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. This transaction is broadcasted to the entire network (Figure 1), and is verified by every node in the network (called “miner” node). The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. The miner node is compensated for their work by a small amount of Bitcoin. The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
The technology of Bitcoin and blockchain has several advantages. The public key is cryptographically generated, allowing for anonymity. Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier. Furthermore, since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain (Wood, 2014), with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.</div>Phamnhhttps://www.clinfowiki.org/wiki/index.php/BlockchainBlockchain2018-10-17T05:23:21Z<p>Phamnh: </p>
<hr />
<div>A blockchain is a public distributed ledgers that maintains a growing list of ordered records (called "blocks") representing transactions that occurred among all interested participants. Each transaction is verified by a majority of the participants before it can be placed in the blockchain. This new transaction is securely linked to the rest of the blockchain. Once it is placed in the blockchain, it can never be erased. Block chain has been applied most famously in creating cryptocurrency, but its application can be extended to any field that values accurate and secured record keeping including banking, accounting, notary, health record keeping, etc. Multiple white papers have been published to discuss the application potential for blockchain in healthcare and research.<br />
<br />
== History of Blockchain ==<br />
<br />
<br />
<br />
== The Technology Behind Blockchain ==<br />
<br />
Since its introduction in 2008 by Satoshi Nakamoto (Nakamoto, 2008), blockchain has been receiving a lot of attention due to its application in cryptocurrency. The most popular example of blockchain technology is Bitcoin, a type of virtual currency that uses cryptographic proof instead of a third-party verifier (such as a banking system) to confirm transaction (Crosby, Pattanayak, Verma, & Kalyanaraman, 2016). Each user of Bitcoin is given a “public key” and a “private key.” When a transaction occurs, a digital signature created from the private key of the sender is sent to the public key of the receiver. This transaction is broadcasted to the entire network (Figure 1), and is verified by every node in the network (called “miner” node). The verification process includes confirming the sender’s identity by checking the digital signature, and making sure that the sender has sufficient fund by checking all of prior transactions involving the sender. To allow for all nodes to participate in the verification process, each miner node must go through a time-delay process that involves solving a mathematical puzzle before its work can be accepted. This is called “proof-of-work” since it takes computing power to solve the puzzles. The miner node is compensated for their work by a small amount of Bitcoin. The transaction is recognized when more than half (at least 51%) of the nodes agree that it is valid. This transaction is now recorded in a block, then added to the top of the ledger, linking to the last block in the ledger by adding to itself a hash made from the prior block. This is called the “blockchain.” All nodes in the network has a copy of the ledger, which will be updated simultaneously when transaction is confirmed. If a ledger differs from the majority, it will be updated to reflect the most up-to-date ledger. This is the blockchain concept of “distributed ledger.”<br />
<br />
[https://assets.weforum.org/editor/_DRLsawgrOCG3OwH3VP4o9VuR4HMAsBeRGFZSo_7RPk.png Figure 1. How Blockchain works]<br />
<br />
The technology of Bitcoin and blockchain has several advantages. The public key is cryptographically generated, allowing for anonymity. Because the ledger is widely distributed and updated based on consensus, it is extremely difficult to manipulate it outside of the verification process, preventing fraudulent transaction without the need of a third-party verifier. Furthermore, since every transaction is recorded in the ledger, the flow of currency is transparent and can be verified by anyone.<br />
While the verification of Bitcoin involves simple calculations to adjust the balance of the sender and receiver after the transaction has been verified, there has been other cryptocurrencies such as Ethereum which take this further and run arbitrary user-defined programs on the blockchain (Wood, 2014), with the purpose of creating a “smart contracts.” The smart contract is an agreement between parties that is enforced automatically by the program. The person who requests the contract deposit currency into the program, which will wait until a certain condition is met before validating it and transfer the currency to the person who carried out the contract. If the condition is not met, the currency is refunded. This technology eliminates the need for a third party to enforce the contract.<br />
<br />
== Application of Blockchain in Healthcare and Research ==<br />
<br />
Blockchain has been proven to be a useful platform for financial transactions. However, its application goes beyond the financial system. Melanie Swan predicts three phases of blockchain adoption: Blockchain 1.0, 2.0, and 3.0 (Swan, 2015). Blockchain 1.0 manifested as online currency. Blockchain 2.0 is the near future, where blockchain is used to keep track of contracts, financial records, public records, and ownership of property. Blockchain 3.0 will be applied into science, medicine and education. <br />
Even though we are still at an early stage of applying blockchain into health care, there are multiple proposals for its application. The majority of these proposals leverage blockchain’s ability to maintain an immutable record to place control of patient’s health record into their hand by allowing them to grant and revoke access to their medical records according to their preference (Gordon & Catalini, 2018; Yue, Wang, Jin, Li, & Jiang, 2016). In a traditional system, patient’s health record is kept and maintained by a health care organization (e.g. hospital, clinic, etc.). Information can be freely shared between the organization and a Regional Health Information Organization (RHIO) or another organization that has a business agreement with the originating institution. If there is no business agreement between the institutions, one-off requests can be made, but this will take time and delay care (Figure 2A). As Meaningful Use Stage 3 is being implemented at health care organizations, there has been a push to create patient-facing application programming interfaces (APIs) that allow patient to directly retrieve their record from the institution and share it with the provider as needed (Figure 2B). Gordon et al. proposes a blockchain-enabled smart contracts controlled by the patient to authorize direct sharing of medical record between institutions (Figure 2C). Patient can specify the subset of the record to be shared or set an expiration date on the authorization.<br />
<br />
Gordon et al. suggested five features of block chain that allow for successful patient-driven interoperability: digital access rules, data aggregation, data liquidity, patient identity, and data immutability. The blockchain-enabled digital access rule is centralized, which makes it accessible by multiple institutions, while facilitating editing of the rules by the patient at any moment via a smart phone-based or web-based application. Patient could also aggregate their data (or metadata) across institutions to a blockchain or another secured location using the digital access rule, thus creating a complete record of their health. Because the change in digital access rules will take effect as soon as the patient (or legal representative) approves it, data can be share rapidly to the requesting institution, allowing access to time-sensitive information such as allergies, “code status,” etc. Even though there is no national patient identifier, institutions can use the blockchain-assigned individual’s public key and match it with their local identifier to start sharing data across systems. Finally, since all changes made to the blockchain is recorded and immutable, the risk of loss is minimized, and the record can be audited at any time. <br />
<br />
Another application for blockchain is in clinical research. A problem that has plagued research is the lack of reproducibility (Ioannidis, 2005), which could be from multiple types of errors, misconduct or fraud. Blockchain offers a solution to this problem by providing an ability to track, share and care for data (Benchoufi & Ravaud, 2017). A recent study has shown that 80% of US employees would share their medical data provided privacy and security can be ensured (Chu). With blockchain-enabled data access rules, patient can easily allow researchers to gain access to their anonymized data, thus increasing the scope and sample size of the clinical research. The integrity of the clinical trial phase can also be maintained by entering each step of the trial with a time stamp into a blockchain and, using smart contract, only allow the next step to be validated after the preceding steps has been fully validated (Figure 3). This will avoid post-hoc data manipulation and posteriori calculus bias. Upon completion of the trial, the publication can be sent along with the link to the block chain which verifies that the study protocol has been followed as it was designed. The blockchain is also readily available to anyone who wants to evaluate validity of the study.<br />
<br />
== Limitations and Proposed Solution ==<br />
<br />
As exciting as the potential for application of blockchain in healthcare is, there remains a number of limitations of blockchain that prevents its widespread use. This section will discuss the different challenges inherent in the first iteration of blockchain and provide possible solutions to them.<br />
<br />
The first concern with block chain is its inability to handle the transaction volume of clinical data. Blockchain is great at keeping a record of changes to a small amount of data (such as account balance, owner’s identity, etc.). However, it is not economically practical to store a large amount of data on the blockchain due to cost associated with creating a very large ledger to store this information and to perform proof-of-work on this ledger. One way to overcome this barrier is to validate data using a different approach to consensus such as proof-of-stake (Siim). Another proposed solution is to store a summary of, instead of a complete clinical report (Gordon & Catalini, 2018). Alternatively, patient’s data can be stored on a permissioned (private) regional blockchains that are built to handle large transaction volumes without time-intensive validation.<br />
<br />
A second limitation of blockchain is the lack of privacy and security. Even though the identifier on the blockchain is the cryptographically generated public key, this is only pseudonymous, as patient can still be identified by matching for other basic demographic information, and once the public key has been linked to the patient, their activity on the blockchain can be tracked. A proposed solution is to use permissioned (member-only) blockchain to avoid public exposure. Basic demographic information stored on a block chain can be encrypted to prevent access as well. Another way to minimize exposure is to store sensitive data off-chain, with on-chain data focusing on granting permission to access requested data using pointers and metadata. This would also allow patients to assign different access rule for different users of their data<br />
<br />
Since the focus of many blockchain-based projects is on patient-controlled health care data, it necessitates more patient participation than the traditional, institution-based paradigm. They must be able to assign certain permissions for different institutions that request access. Having a patient-friendly “app” to manage public keys and permissions will become very important to get more buy-in from patients. Furthermore, patient will also need to keep track of their password to gain access to their private key in order to make changes to the block chain. There will need to be a mechanism for recovering lost password when this occurs.<br />
<br />
Finally, the largest barrier to widespread adoption of blockchain in healthcare deals with the issue of incentives. Meaningful Use stage 3 requires implementation of patient-facing API, but this does not entail handling access control of healthcare record to patient. Institution has little incentive to pay for the cost of setting up a blockchain just to give patient more control even though this will improve interoperability. One solution is expanding federal incentives to patient-controlled medical record. Alternatively, researchers can be incentivized to pay for the setup of these blockchains by gaining access to patient anonymized data for research purposes.</div>Phamnh