Electronic Health Records (EHRs) are entirely controlled by hospitals, not patients, making it difficult to obtain medical advice from individual hospitals. Patients need to keep tabs on their health details and take back control of their medical data. The rapid development of blockchain technology has facilitated large-scale healthcare, including medical records and patient-related data. The technology provides comprehensive and immutable patient records and free access to electronic medical records for providers and treatment portals. To ensure the validity of the blockchain-connected EHR, the Improved Attribute-Based Signature Scheme (IASS) has considerable powers, allowing patients to approve messages based on attributes but not validated. In addition, it avoids the problem of having multiple authorities without a single or central source of trust for generating and distributing patient public/private keys and fits into the blockchain model for distributed data storage. By sharing a secret, pseudo-random activity seed between authorities, the protocol resists collusive attacks by corrupt officials. The technology provides patients with a comprehensive, immutable record and free access to their EHR from providers and treatment portals. To ensure the validity of blockchain-connected EHRs, propose an attribute-based multi-authority signature scheme that authorizes messages based on their attributes without revealing any information
