The medical and healthcare professionals need to maintain accurate health records of the patients, and these records need to be shared among different medical and healthcare institutions so that the medical staff can read the medical history comprehensively and avoid missing the important information. At this stage, the medical staff have used Electronic Health Records (HER) as the key to achieving these goals and providing quality care. However, there are still some technical and legal restrictions. The inability to resolve performance and privacy issues has always restricted the development of the industry.

For a long time, people have believed that Electronic Health Records (EHR) should be stored across time and space, and can be accessed at any time within the scope of the law.

In the first stage of digitization, whether Electronic Medical Records (EMR) are on a local server or on the cloud, we are storing the medical history of the patients within the jurisdiction of the medical and healthcare provider. There is no essential difference between this electronic medical record system and the traditional paper medical record system, because the information technology only transfers the management of medical records from paper to hard disk.

The electronic medical record system cannot be disseminated from one practice, but is transmitted to other practices by fax or signed documents, which is time-consuming.

In the second stage, authorized doctors and staff create, manage and consult electronic medical records of multiple medical institutions, allowing interoperability between different electronic medical record systems. That is, EHR can share information among doctors and track patient information across multiple medical institutions. In the United States, EMR exchange is on a public platform, namely the national health information network. It is a set of standards, services and policies, which can exchange safe health information through the Internet. However, technical and legal problems hinder the application of these systems.

The DNTP (Deltal National Treatment Programme) project was initiated to build an experimental blockchain platform for EHR. It overcomes the shortcomings of the traditional EHR system and is also different from other EHR blockchains. It is an alliance composed of multiple organizations, namely hospitals, insurance providers, and government agencies. The business logic is determined by the management model allowed by the alliance, rather than the unreliable model of other medical blockchains;

Specifically, the differences between the proposed DNTP and other EHR blockchains are:

First of all, DNTP is an alliance. The business logic is determined by the management model allowed from the beginning of the alliance, rather than the unreliable model of other medical blockchains.

Secondly, DNTP performs well in the following aspects: data availability, data integrity, and retrieval success rate, that is, even if a small number of servers crash, DNTP is always online.

The real electronic medical records are stored because they are signed by valid stakeholders. Thanks to load balancing, we can successfully access account books at any time.

More importantly, DNTP uses Proof of Authority (PoA) as its consensus protocol. The designated, authenticated and trusted ordering party is responsible for generating valid blocks, that is, as long as these blocks are signed by one of the ordering parties, they will be accepted by all participants. PoA is different from other consensus protocols, such as Proof of Work and Practical Byzantine Fault Tolerance (PBFT).

Finally, different users have different chain code application programming interfaces (APIs) in DNTP, which are specified by the management model. Therefore, we can define how users interact with account books and implement access control strategies.