A Review of Secure and Privacy-Preserving Medical Data Sharing

In the digital healthcare era, it is of the utmost importance to harness medical information scattered across healthcare institutions to support in-depth data analysis and achieve personalized healthcare. However, the cyberinfrastructure boundaries of healthcare organizations and privacy leakage threats place obstacles on the sharing of medical records. Blockchain, as a public ledger characterized by its transparency, tamper-evidence, trustlessness, and decentralization, can help build a secure medical data exchange network. This paper surveys the state-of-the-art schemes on secure and privacy-preserving medical data sharing of the past decade with a focus on blockchain-based approaches. We classify them into permissionless blockchain-based approaches and permissioned blockchain-based approaches and analyze their advantages and disadvantages. We also discuss potential research topics on blockchain-based medical data sharing.