Fall 2017 issue of Horizons

Other great features of this decentralized ledger technology include data protection, security (through encryption) and standardization. EHR systems could send information packets to the ledger in a standardized format (which would solve the interoperability issue). The figure to the right shows a simple example of a blockchain network. As shown in the figure, each user has a complete copy of the ledger. If a user, say User 5, drops out of the network, there is no impact on the integrity of the ledger as complete copies are still maintained and validated across the four remaining users. In addition to a robust network, blockchain automatically reconciles transactions (or records), as opposed to the very manual process in place today to reconcile records between EHR systems. To understand how blockchain will automatically validate and reconcile medical record data, we have to dive deeper into the fundamental process of chaining blocks of information together to create a ledger. Specifically, each block of data (say, fifteen minutes worth of transactions or records) is given a ‘fingerprint’ or a unique code. Each 15-minute block of information would need to be assigned a code that is consistent with its predecessor (which is done through the use of a cryptographic algorithm) thus “chaining” the blocks of information together. Blockchain would provide the mechanism for EHR systems to not only send packets (or blocks) of information to a decentralized ledger of records of all other EHR systems in the network, but also allows a particular EHR to reference that ledger to pull a continuous log of information about a patient from the network. Forbes points out that one of the nearest term opportunities to apply blockchain technology to healthcare is to create clinical health data exchanges that “are cryptographically secured and irrevocable.”

In a recent whitepaper, A Case Study for Blockchain in Healthcare , a joint team of researchers from the MIT Media Lab and Beth Israel Deaconess Medical Center successfully tested a prototype deployment of blockchain technology, creating a decentralized ledger of prescribed medications.

Block Chain Network

USER 1 NODE

LEDGER

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USER 3 NODE

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USER 5 NODE

LEDGER

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USER 2 NODE

LEDGER

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USER 4 NODE

LEDGER

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Fall 2017

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