Lightweight and Scalable Blockchain-Based Integrity Verification for EHR Systems

Abstract

The modern use of Electronic Health Records (EHRs) has made healthcare useful but it’s growing demand also raised more concerns about data integrity, unauthorised changes, and the ability to audit centralised storage systems. The existing blockchain-based healthcare solutions largely emphasis on sharing data and controlling access and they frequently rely on lot of computational overhead or complicated cryptographic mechanisms that limit their suitability for real time use. To address this we proposed a simple, permissioned blockchain-based system for checking the integrity of EHRs using Hyperledger Fabric and SHA-256 cryptographic hashing without storing sensitive medical data on-chain. Only deterministic hash values of patient records are recorded for tamper-evident verification without giving away private information. The Fabric Certificate Authority makes sure that identity management and access control are restricted only to authenticated and role-based users participate. A proof-of-concept implementation using Docker-based deployment. A quantitative analysis demonstrates that the hashing latency is low (0.005 seconds per record), the time it takes to execute a smart contract is about 50 milliseconds, and the accuracy of tamper detection is 100% when simulated attacks are used. The proposed research gives a practical and scalable method for healthcare systems which make sure that patient privacy is protected and accurate. Many existing blockchain healthcare systems that focus primarily on data sharing or analytics, proposed framework specifically addresses lightweight and real-time integrity verification of electronic health records while minimizing blockchain storage overhead.