A Zero-Knowledge Proof and Differential Privacy-Enhanced Blockchain Framework for Secure Multi-Institutional Electronic Health Record Sharing

Abstract

Secure and private sharing of electronic health records (EHRs) among multiple parties remains a significant challenge in digital healthcare. Although Blockchain technology can ensure data integrity through security and transparency, protecting patient privacy and enabling secure collaborative analysis continue to be difficult problems. To address these challenges, differential privacy (DP) and Zero-Knowledge Proofs (ZKPs) are integrated into a Blockchain-based solution in the innovative design of this multi-institutional EHR-sharing system architecture. ZKPs enable the verification of user identities and access requests without revealing sensitive information, while DP ensures that analytical results are statistically valid and that underlying data are protected against re-identification attacks. A permissioned Blockchain system is developed to support verifiable and privacy-preserving federated analytics over distributed data. Experimental results demonstrate that the proposed framework successfully achieves privacy protection, secure access, and interoperable data-sharing objectives.