Tim Mackey (Fig. 1)
Whether you are a clinician, researcher, entrepreneur, administrator, or executive, you are probably familiar with the term ‘blockchain’. At its core, blockchain is a new type of digital architecture, consisting of a shared, immutable ledger that can better ensure the resilience, provenance, traceability, and management of health data. It has been hailed as a revolutionary technology, but whether it meets this potential remains to be tested.
To understand blockchain’s potential for healthcare, we first need to understand some basic technical elements. Unlike traditional centralized databases, data on a blockchain can be distributed across multiple databases/computers (also known as ‘nodes’) so that everyone has the same copy (ledger) of a transaction [1]. ‘Blocks’ of data are linked together by a hash (a digital signature of random letters and numbers) to form a ‘chain’ of data that contains the complete history of the transaction and renders it tamper resistant [2, 3]. Blockchain data is also secured through cryptography (advanced encryption) so that participants can trust that ‘blocks’ of data are authenticated and verifiable [2]. These technological features result in decentralized data systems (not held by a central authority vulnerable to breach or potentially acting as a single point of failure), represent a single source of information among all participants, and have inherently higher levels of trust (as transactions are immutable, secure, and subject to consensus of the participants). Blockchains can also be permissioned to limit participation and access to or sharing of data [4]. Finally, there are public blockchains (e.g., public network-based blockchains such as the popular cryptocurrency Bitcoin) and private or ‘business’ blockchains (e.g., private networks not open to the public but instead used by a select group of trusted participants) [5]. Some popular platforms for blockchain deployment include Ethereum and Hyperledger, though offerings are growing.
Beyond these core features, blockchains can also enable other technologies such as distributed applications (those that run on multiple computers in a network) and smart contracts (computer code that can execute terms of a contract between parties) as well as the use of cryptocurrencies (digital or virtual currencies) [2, 6,7,8]. Blockchains can also act as a digital backbone for other technologies able to interface with blockchain systems such as cloud computing, artificial intelligence, eHealth and mHealth devices/applications, and the broader Internet of Medical Things (IoMT) [6, 9, 10]. Thus, the blockchain environment is expansive and modular, and has the flexibility to be adopted for various use cases in healthcare and beyond (see technology architecture summary in Fig. 2).
Reflecting the increased attention given to blockchain in healthcare and life sciences, the number of PubMed indexed articles including the keyword ‘blockchain’ in the title or abstract fields has increased dramatically, from only 5 in 2016 to 64 in 2018 (Fig. 3). The published papers evidence the wide variety of use cases that are being researched for health blockchains, including management and interoperability of healthcare data (e.g., patient healthcare, consumer health, and hospital data), improving integrity of published research, clinical trial management, use and integration into IoMT applications (including mHealth and remote patient monitoring), advancing genomics and precision medicine, applications for biomedical and medical education and research, pharmaceutical supply chain management and security, implications of blockchain for global health, and general articles of the various opportunities for blockchain in medicine, engineering and the life sciences [3,4,5, 7, 11,12,13,14,15,16,17,18,19,20,21,22,23,24]. However, it is important to note that the published literature represents only a snapshot of global blockchain activity, as many health-related blockchain projects are published in white papers, news articles, press releases, presented at conferences, or are otherwise undisclosed as they are developed for commercialization purposes. Several large technology firms, such as IBM, Intel, and Microsoft, are heavily invested in blockchain technology development, and the World Economic Forum estimates that, by 2025, 10% of the global gross domestic product will be stored on blockchain technology [25].
Despite blockchain’s potential as an emerging technology to be innovative and disruptive, it remains immature, particularly in healthcare. According to Gartner [26], blockchain technology is in a ‘hype cycle’ characterized by stages of innovation triggers, inflated expectations, disillusionment, enlightenment, and ending in a “plateau of productivity”, with healthcare and life sciences currently squarely in the middle of phase one and two of the curve. Reflecting the fact that it is still early days for health blockchains, there are few real-world examples of blockchain systems that have gone into production and that also have strong commercial or user adoption in healthcare. In contrast, other sectors of the economy have seen much faster adoption, including financial technology services and supply chain and logistics.
Despite the core characteristics of decentralization, security, provenance, transparency, trust, and better management of data being clear benefits to address acute healthcare needs, an approach that ensures that blockchain technology is ‘fit-for-purpose’ for specific and diverse healthcare challenges is required. Importantly, when assessing the viability of a blockchain for health, what core blockchain characteristics and design principles need to be taken into account, and how can they address the real-world legal, regulatory, privacy, business, and provider and patient-centric considerations unique to healthcare?
In an attempt to address these challenges, this Forum article presents a ‘fit-for-purpose’ health blockchain design framework that includes fundamental questions regarding basic blockchain design principles, data sharing and management, and decisions about governance, as well as exploring the technologies that can be used to enhance blockchain function and defining the ultimate goal for the blockchain solution. If these questions can be appropriately mapped, then there is a higher likelihood that the blockchain approach will be ‘fit-for-purpose’ for whatever healthcare challenge has been identified. The framework questions are based on six principles, as follows:
-
1.
Blockchain design types: Decision of whether your blockchain design will be a public blockchain (generally open to participation by anyone and not permissioned), private blockchain (involving limited participation and having permission structures), or a hybrid (blockchain systems with both public and private designs).
-
2.
Data sharing and access: In healthcare, sharing and access to health-related data is subject to various privacy, legal, and regulatory requirements (such as the Health Insurance Portability and Accountability Act (HIPAA) and the General Data Protection Regulation (GDPR)). Decisions need to be made about what type of data will be shared with and among participants, if any, whether data will be stored on-chain, off-chain or on a side-chain, and the type of permission structures that will be utilized.
-
3.
Decisions about blockchain governance: Governance is a crucial component to the design of a blockchain system. The nodes, users, peers, and/or validators of the blockchain will need to be defined, as well as whether it will be comprised of only trusted partners, a consortium of participants, or participation of public entities or regulators, and include patients/consumers/the public. Finally, how these actors will make decisions about how to govern the blockchain (including choices regarding consensus mechanisms, permissions, and data governance) will also need defining.
-
4.
Added technology to enhance blockchain function: As previously discussed, the blockchain architecture can also enable the use of other technologies, including the development of an application layer that interfaces with the blockchain, the use of smart contracts to automate processes when certain agreed upon conditions are met, and the use of a cryptocurrency/tokens to incentivize participation that ideally provides shared benefits to all participants.
-
5.
Ultimate healthcare goal of the blockchain: Although it may seem obvious, a critical issue that must be addressed is the definition of the ultimate goal of the blockchain to improve healthcare. Beyond the core benefits of a distributed, immutable, transparent, and higher trust system, the unique benefits a blockchain system can provide for healthcare processes over other existing technologies must also be assessed. Not all blockchains will have the same goal(s). For example, some may be designed to simply lower healthcare transaction-related costs by improving and automating processes (such as the use of smart contracts), removing intermediaries, or reducing administrative burden. Others may focus on creating mechanisms to drive revenue generation. Some will prioritize enabling better data collection, use, and sharing from patients, consumers, and providers through the offer of incentives (such as tokens). Further, others may focus on more indirect benefits such as increasing compliance or preventing fraud. Eventually, some blockchains may be designed to achieve multiple goals, yet may start with the most pragmatic use first.
-
6.
The need for a blockchain: A final question may simply ask whether the healthcare-related challenge or goal really needs a blockchain, or if it can be better facilitated by another form of technology.
Though the above ‘fit-for-purpose’ blockchain framework considerations are not exhaustive, they form a basis for thinking about how blockchains can be designed in ways that have shared goals of improving healthcare and ultimately patient outcomes. Using this framework as a starting point, this article introduces a set of prominent use cases in healthcare to further examine what a ‘health’ blockchain may look like in the near future based on ongoing research, published studies, and real-world examples. The aim of this article is to explore different perspectives about key design elements, challenges, opportunities, and best practices for the future health blockchain landscape. To accomplish this, the article brings together a diverse and multidisciplinary group of experts from academia, the private sector, healthcare startups, and professional technology associations to discuss use cases in healthcare records, clinical trial management, medical credentialing and licensing, genomics and precision medicine, pharmaceutical supply chain, and biomedical research. It closes with a discussion from the IEEE Standards Association about the importance of setting technical and industry standards to ensure blockchain in healthcare moves forward and realizes its potential as a revolutionary force for 21st century healthcare.