Electronic health records (EHRs) play an important role in our life. However, most of the time, they are scattered and saved on different databases belonging to distinct institutions (hospitals, laboratories, clinics, etc.) geographically distributed across one or many countries. Due to this decentralization and the heterogeneity of the different involved systems, medical staff are facing difficulties in correctly collaborating by sharing, protecting, and tracking their patient’s electronic health-record history to provide them with the best care. Additionally, patients have no control over their private EHRs. Blockchain has many promising future uses for the healthcare domain because it provides a better solution for sharing data while preserving the integrity, the interoperability, the availability of the classical client–server architectures used to manage EHRS. This paper proposes a framework called HealthBlock for collaboratively sharing EHRs and their privacy preservation. Different technologies have been combined to achieve this goal. The InterPlanetary File System (IPFS) technology stores and shares patients’ EHRs in distributed off-chain storage and ensures the record’s immutability; Hyperledger Indy gives patients full control over their EHRs, and Hyperledger Fabric stores the patient-access control policy and delegations.

Electronic Health Records (EHRs) play an important role in our life. However, most of the time, they are scattered and saved on different databases belonging to distinct institutions (hospitals, laboratories, clinics, etc.) geographically distributed across one or many countries. Due to this decentralization and the heterogeneity of the different involved systems, the medical staff are facing difficulties in correctly collaborating by sharing, protecting, and tracking their patient’s electronic health-record history to provide them the best cares. Also, patients have no control on their private EHRs. Blockchain has many promising futures useful for the healthcare domain because it provides a better solution for sharing data while preserving the integrity, the interoperability, the availability, and even the privacy than classical client-server architectures used to manage EHRS. This paper proposes a modular framework called HealthBlock for a collaborative sharing EHRs and their privacy-preserving with a granular access control. Different technologies have been combined to access this goal. the InterPlanetary File System (IPFS) technology stores and shares patients’ EHRs in distributed Off-Chain storage and ensures the record’s immutability; the Hyper-ledger Indy gives patients full control over their EHRs and the Hyper-ledger Fabric store the patient access control policy and delegations.