A Review on the Role of Blockchain Technology in the Healthcare Domain

electronics Review A Review on the Role of Blockchain Technology in the Healthcare Domain Haider Dhia Zubaydi 1 , Yung-Wey Chong 1, * , Kwangman Ko 2 , Sabri M. Hanshi 1 Shankar Karuppayah 1 1 2 * and National Advanced IPv6 Centre, Universiti Sains Malaysia, Gelugor 11800, Penang, Malaysia; (H.D.Z.); (S.M.H.); (S.K.) School of Computer and Information Engineering, Sangji University, Gangwon 220-702, Korea; Correspondence: Received: 31 March 2019; Accepted: 12 May 2019; Published: 15 June 2019



 Abstract: Recently, there have been increasing calls for healthcare providers to provide controls for patients over their personal health records. Nevertheless, security issues concerning how different healthcare providers exchange healthcare information have caused a flop in the deployment of such systems. The ability to exchange data securely is important so that new borderless integrated healthcare services can be provided to patients. Due to its decentralized nature, blockchain technology is a suitable driver for the much-needed shift towards integrated healthcare, providing new insights and addressing some of the main challenges of many healthcare areas. Blockchain allows healthcare providers to record and manage peer-to-peer transactions through a network without central authority. In this paper, we discuss the concept of blockchain technology and hurdles in their adoption in the healthcare domain. Furthermore, a review is conducted on the latest implementations of blockchain technology in healthcare. Finally, a new case study of a blockchain-based healthcare platform is presented addressing the drawbacks of current designs, followed by recommendations for future blockchain researchers and developers. Keywords: blockchain; blockchain-based platform; DApp; decentralized application; healthcare; Internet of Things; IoT 1. Introduction Blockchain is a digital-ledger-based technology developed to change the perspective of the digital transactions, or specifically, to replace them. Blockchain is defined as a distinct, decentralized distributed ledger that includes all transactions records related to participating members. Blockchain transactions are created and stored in chronological order [1], allowing digital assets (such as digital currency and digital data) to be tracked by participants without central record-keeping [2,3]. One of the key features in blockchain is that participating nodes in the network will hold a copy of the full blockchain [4]. All transactions on the blockchain must be approved because transactions are only valid under the consensus agreement of the participating members. In addition, all transactions are trackable [5], making fraudulent transactions impossible to bypass [6]. When a user (user A) wants to make a transaction to another user (user B) using blockchain, a new block is created to include the transaction. Each transaction is broadcasted across network nodes to verify it. If the new transaction is verified, the new block is added to the blockchain and distributed across network nodes so that other nodes will update their blockchain. Finally, the transaction is received by another user (user B). The full process is depicted in Figure 1. Electronics 2019, 8, 679; doi:10.3390/electronics8060679 www.mdpi.com/journal/electronics Electronics 2019, 8, 679 2 of 29 Figure 1. Blockchain process. The launch of the Ethereum platform blockchain [7,8] enabled blockchain to support transactions in numerous applications besides cryptocurrency [9,10]. Most healthcare applications are developed on the Ethereum framework [11]. Blockchain technology is considered a promising technology for many areas such as public services [12], reputation systems [13], Internet of Things (IoT) [14], and security services [15]. Blockchain-based applications utilise smart contracts [16] to store any record or transaction of value such as currency, oil, gold, real estate contracts, energy, and intellectual property rights (IPR). Blockchain technology has two distinct characteristics: anonymity and distributed consensus [17]. Blockchain transactions provide many advantages such as security, decentralization, and instant transactions. This is because Blockchain technology (BT) eliminates the need for intermediary points such as agents or brokers. Since data is an asset in the digital economy, it is crucial to ensure that data in specific applications have not been manipulated or corrupted. Throughout the years, Blockchain has gone through extensive development, namely digital currency (Blockchain 1.0), digital economy (Blockchain 2.0), and digital society (Blockchain 3.0). The first generation is related to the underlying technology platform (i.e., public ledger, hashing, Electronics 2019, 8, 679 3 of 29 and mining) and overlying protocols (transaction enabling software) to support digital currency [6]. The concept of second generation Blockchain was proposed by [18] as an infrastructure for more complex application (i.e., mortgages, derivatives, stocks, and assets that can be monetized). The major innovation of the second generation relies on the usage of Blockchain in managing assets and trust agreements; thus, the concept of smart contracts was conceived. Smart contracts are an emerging use case in this generation, and are defined as computer programs that automatically execute contract terms and manage smart properties [19]. Smart contracts are faster for execution and data can be transferred faster as compared with traditional contracts [20], making it a key feature in Blockchain technology. Blockchain applications unrelated to economic activity, financial markets, commerce or money are referred to as digital society or Blockchain 3.0 [6]. This generation is associated with broader applications such as education health, science, art and governance. In this generation, several technologies are integrated with blockchain, such as cyber physical systems. In recent years, blockchain technologies have been applied in Electronic Medical Records (EMR) systems to provide control, supervision, accessibility, auditability, and interoperability over large scale data management frameworks using a comprehensive log. Current blockchain technology enables sharing and consuming computing resources, and delivering computing capabilities anytime, anywhere [9]. It is expected to revolutionize and drive industry and economics because it is secure, fast, trustworthy, immutable, and provides public and private transparent solutions. Transactions on the blockchain ameliorate the need for documentation, duplication, third-party intervention, and remediation. Although blockchain has been used in various applications for secure transactions, there are different challenges that need to be considered when implementing blockchain in healthcare application [21,22]. This is because healthcare is a regulated domain that involved patient’s privacy. In this paper, prob (...truncated)