By Giulia D'Alessandro
Medical data contains multiple records of patient data that are important for subsequent treatment and future research. However, it needs to be stored and shared securely to protect the privacy of the data. One feasible solution is the blockchain. Blockchain is widely used in the management of healthcare data because of its decentralized and tamper-proof features.Healthcare data is relevant to everyone as it records physical information about our bodies, among other things. It is also important for the diagnosis and treatment of diseases. With the rapid development of artificial intelligence, medical data has become a great asset. For instance, it can help us build artificial intelligence diagnostic models and assist doctors in diagnosis. Although the recording of medical information has evolved from the initial paper records to electronic medical records (EMR), which are more convenient for data access and storage, more attention needs to be paid to protecting data privacy. Many hospitals and institutions have reduced data transfer and sharing in order to avoid data privacy leakage. These have prompted the search for secure data storage and transmission methods, and blockchain is widely used, because of its decentralized, tamper-proof nature, for sharing medical data.
Blockchain has been widely noticed especially since the first appearance of Bitcoin, one of the most popular forms of cryptocurrencies, in 2008. It consists of a chronological database in which all contents can be verified. The blockchain is encrypted and organized into blocks. Each block contains info about several transactions, a reference to the previous block, and the answer to a complex algorithm used to verify data from that block. Once information is entered into the system, it cannot be changed. Thanks to its decentralization, it is virtually impossible for the blockchain to be the target of hacking activities. Further, any change in the registry requires the consent of all participants in the network. This is why it is considered one of the most reliable tools to protect sensitive data.
There are many situations in which blockchain is used in medical data sharing. As we speak, there exist three types of blockchain according to the application scenarios:
blockchain-based data security storage and access - this model uses the blockchain as a database to store the complete case information of the patient in the block. The transaction records are hashed to store the obtained hash values in the Merkle tree to ensure the security of the data and prevent tampering, thus reducing errors in clinical decision-making. Then, blockchain technology is used to build a private information storage platform, and standard cryptographic algorithms are used to realize information transmission.
use of blockchain combined with IOMT (Internet Of Medical Things) - the IOMT includes various medical devices that use computer networks to connect and detect the parameters of patients. IOMT brings great advantages for patients’ disease management, and the detection of physical signs can detect diseases as soon as possible to seek medical treatment. However, IOMT products are prone to information leakage. Blockchain brings a solution for the security of medical IOMT. An IOMT-based data acquisition system has been developed to achieve secure storage and sharing of medical data. This system developed as a cloud server-based anonymous medical data sharing scheme, can collect data from several medical devices simultaneously to achieve real-time collection of patient health records during surgery.
use of blockchain to replace the central institution of federal learning - federated learning is a new AI technique that protects data privacy when building AI models. It enables multiple nodes to learn a model together without sharing the data with other devices. However, with this system, data needs to be shared with a central institution. Blockchain can be a good alternative to the central institution and avoids the dishonesty of the central structure. Also, each transaction is recorded on the chain, which enables the timely detection of malicious nodes and provides oversight.
In general, traditionally sensitive medical data are protected using cryptography. This method has proven to be unsafe because of the high risk of secret key leakage when there are several organizations to share it with. On the contrary, the blockchain-based model enables secure access with the use of smart contracts. So, the decentralized, traceable, and tamper-proof nature of blockchain has made it of great interest in the field of healthcare data. Compared with the traditional cryptography-based model, the blockchain-based model is more secure and intelligent because smart contracts play an important role in the protection of sensitive data. More analyses, investments, and efforts should be promoted in this sector to improve the overall condition of the healthcare system.