Blockchain-Assisted Electronic Medical Data-Sharing: Developments, Approaches and Perspectives

Medical blockchain data-sharing is a technique that employs blockchain technology to facilitate the sharing of electronic medical data. The blockchain is a decentralized digital ledger that ensures data-sharing security, transparency, and traceability through cryptographic technology and consensus algorithms. Consequently, medical blockchain data-sharing methods have garnered significant attention and research efforts. Nevertheless, current methods have different storage and transmission measures for original data in the medical blockchain, resulting in large differences in performance and privacy. Therefore, we divide the medical blockchain data-sharing method into on-chain sharing and off-chain sharing according to the original data storage location. Among them, off-chain sharing can be subdivided into on-cloud sharing and local sharing according to whether the data is moved. Subsequently, we provide a detailed analysis of basic processes and research content for each method. Finally, we summarize the challenges posed by the current methods and discuss future research directions.