Abstract
Background: Health information exchange (HIE) is critical for coordinated care but faces persistent security and interoperability challenges. Blockchain technology has emerged as a promising solution to enhance data integrity, access control, and patient privacy. This systematic review synthesizes the current evidence on blockchain-based approaches for secure HIE.Methods: We conducted a systematic literature search in PubMed, IEEE Xplore, Scopus, and Web of Science for articles published between 2015 and February 2024. Inclusion criteria were peer-reviewed studies proposing, implementing, or evaluating blockchain frameworks for HIE. Two reviewers independently screened 1,247 records, yielding 36 eligible studies. Data extraction focused on architectural models, security mechanisms, interoperability solutions, and reported outcomes.Results: The review identified three primary architectural patterns: permissioned blockchain with off-chain storage, hybrid on-chain/off-chain designs, and decentralized identifiers combined with smart contracts. Key security features included cryptographic hashing, digital signatures, and attribute-based access control. Interoperability was addressed via standardized APIs and cross-chain protocols. Performance evaluations reported transaction latencies ranging from 0.5 to 5 seconds and throughputs up to 1,000 transactions per second. Patient consent management and auditability were consistently highlighted as strengths. However, scalability, regulatory compliance, and integration with legacy systems remain significant challenges.Conclusions: Blockchain offers a robust foundation for secure HIE, particularly in managing consent and ensuring data provenance. Future research should focus on large-scale deployments, interoperability standards, and usability studies. Policymakers and healthcare organizations should consider pilot implementations to evaluate real-world feasibility.
Keywords
blockchain, health information exchange, security, interoperability, electronic health records, systematic review, privacy, smart contracts