Design Choices and Trade-Offs in Health Care Blockchain Implementations: Systematic Review

Abstract

Background A blockchain is a list of records that uses cryptography to make stored data immutable; their use has recently been proposed for electronic medical record (EMR) systems. This paper details a systematic review of trade-offs in blockchain technologies that are relevant to EMRs. Trade-offs are defined as “a compromise between two desirable but incompatible features.” Objective This review’s primary research question was: “What are the trade-offs involved in different blockchain designs that are relevant to the creation of blockchain-based electronic medical records systems?” Methods Seven databases were systematically searched for relevant articles using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Papers published from January 1, 2017 to June 15, 2018 were selected. Quality assessments of papers were performed using the Risk Of Bias In Non-randomized Studies—of Interventions (ROBINS-I) tool and the Critical Assessment Skills Programme (CASP) tool. Database searches identified 2885 articles, of which 15 were ultimately included for analysis. Results A total of 17 trade-offs were identified impacting the design, development, and implementation of blockchain systems; these trade-offs are organized into themes, including business, application, data, and technology architecture. Conclusions The key findings concluded the following: (1) multiple trade-offs can be managed adaptively to improve EMR utility; (2) multiple trade-offs involve improving the security of blockchain systems at the cost of other features, meaning EMR efficacy highly depends on data protection standards; and (3) multiple trade-offs result in improved blockchain scalability. Consideration of these trade-offs will be important to the specific environment in which electronic medical records are being developed. This review also uses its findings to suggest useful design choices for a hypothetical National Health Service blockchain. International Registered Report Identifier (IRRID) RR2-10.2196/10994

Bridges Between Islands: Cross-Chain Technology for Distributed Ledger Technology

“…However, several challenges withhold the development of more powerful applications built on DLT. Developers face inherent trade-offs between DLT characteristics (e.g., availability vs. consistency [16,26]), which is why the fulfillment of one DLT characteristic may impede others [26]. Consequently, while one DLT design can be well suited for a particular use case, it may not fit other use cases, ultimately inhibiting the development of a one-size-fits-all DLT design, and fueling the emergence of diverse DLT designs (e.g., Ethereum, IOTA, or Tezos) [16], each operating separately.…”

Scalability Challenges in Healthcare Blockchain System—A Systematic Review

“…This review focuses on how blockchain addresses scalability challenges and provides solutions in the healthcare field through the implementation of blockchain technology. However, several challenges persists, including the number of nodes [10], [15], [19], [27], [28], transactions [9], [10], [15], [28]- [30], high volume of data [13], [20], [30], [32], [33], protocol challenges [9], [10], [15], [28], [34], and block size [10], [12], [30]. To achieve productive benefits, current technology should be developed by solving these challenges.…”

Do Not Be Fooled: Toward a Holistic Comparison of Distributed Ledger Technology Designs

“…Such DLT designs specialize in fulfilling requirements of a particular set of applications on DLT in domains such as the Internet of Things (IoT), finance, and supply chain management. However, this specialization resulted in trade-offs between DLT characteristics that restrict the suitability of a DLT design to a particular set of applications [1,2]. For example, a DLT design cannot provide high availability and a high degree of consistency simultaneously because a large number of nodes of the ledger, which is needed for high availability, requires more time and effort to be synchronized, thereby challenging consistency [1,2].…”

“…However, this specialization resulted in trade-offs between DLT characteristics that restrict the suitability of a DLT design to a particular set of applications [1,2]. For example, a DLT design cannot provide high availability and a high degree of consistency simultaneously because a large number of nodes of the ledger, which is needed for high availability, requires more time and effort to be synchronized, thereby challenging consistency [1,2]. Due to the prevalent trade-offs between DLT characteristics, the improvement of one DLT characteristic deters another, inhibiting a one-size-fitsall DLT design suiting all requirements of individual applications.…”

“…Due to the prevalent trade-offs between DLT characteristics, the improvement of one DLT characteristic deters another, inhibiting a one-size-fitsall DLT design suiting all requirements of individual applications. Trade-offs thus require developers to choose the best fitting DLT design for their application [2]. Making careful and well-founded decisions in favor for an (appropriate) DLT design to develop viable applications on DLT becomes even more crucial because technical differences between DLT designs (e.g., different data structures and consensus mechanisms) impede the ex-post migration of data stored on one distributed ledger to another [3].…”