Deletion and Recovery Scheme of Electronic Health Records Based on Medical Certifificate Blockchain

The trusted sharing of Electronic Health Records (EHR) can realize the effiffifficient use of medical data resources. Generally speaking, EHR are stored inside the hospital, but their ownership is the patient, So every patient has the right to delete their own EHR stored in the hospital. However, after the deletion, it is diffiffifficult for the patient to have a record to share when he visits the hospital again. To solve this problem, we use the Medical Certifificate Blockchain and InterPlanetary File System (IPFS) to store Personal Health Records, which are generated by patients in difffferent medical institutions. We use cross-chain technology to interconnect the Medical Certifificate Blockchain and the Hospital blockchain to enable the recovery of deleted Electronic Health Record. In addition, We also combine digital watermarking technology to ensure the authenticity of the restored Electronic Health Record. System analysis and security analysis illustrate the completeness and feasibility of the scheme.