A privacy preserving medical data management framework using blockchain enabled encrypted role based access control

The fast computerization of health care has created the issue of data leakage, unauthorized access and patient loss of trust. As Electronic Health Records (EHRs) become the focus of clinical processes, data protection, security, and auditing have become a matter of concern. Conventional centralized medical records are still vulnerable to single points of vulnerability, untraceability, and misuse of privileges, resulting in data breach and lack of trust of security in health care data management. To mitigate these problems, this study will propose a privacy-sensitive medical data management system based on blockchain technology to offer secure, transparent, and role-based access to EHRs. The framework combines multi-layer cryptographic security, decentralized authorization through smart contracts, and encrypted storage with the InterPlanetary File System (IPFS) to secure confidentiality and scalability. Access transactions are stored verifiably and tamper-resistant on the blockchain, which does not affect efficiency. Based on the UCI Heart Disease data, the framework was able to attain 98.5% access success, 220 access requests/sec, and 96% privacy retention rates, which is 12-15 times higher than traditional centralized EHR systems. These findings illustrate a robust, scalable and privacy ensuring alternative that guarantees integrity, accountability and efficiency of operations in medical data sharing.