%0 Journal Article
%@ 1438-8871
%I JMIR Publications
%V 21
%N 5
%P e12426
%T Design Choices and Trade-Offs in Health Care Blockchain Implementations: Systematic Review
%A O'Donoghue,Odhran
%A Vazirani,Anuraag A
%A Brindley,David
%A Meinert,Edward
%+ Healthcare Translation Research Group, Department of Paediatrics, University of Oxford, Level 2, Children's Hospital, John Radcliffe Hospital, Oxford, OX3 9DU, United Kingdom, 44 7824446808, edward.meinert@paediatrics.ox.ac.uk
%K blockchain
%K interoperability
%K distributed ledger technology
%K scalability
%K health information exchange
%D 2019
%7 10.05.2019
%9 Review
%J J Med Internet Res
%G English
%X 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 
%M 31094344
%R 10.2196/12426
%U https://www.jmir.org/2019/5/e12426/
%U https://doi.org/10.2196/12426
%U http://www.ncbi.nlm.nih.gov/pubmed/31094344