Best Practice Methods for Living Evidence Synthesis in Health Care: An International Modified Delphi Survey

Background Living evidence syntheses (LES) represent continual updates for an important topic for decision-making where there is uncertainty in the evidence. Whereas best practices for traditional evidence syntheses in health care are well established, they are not for LES. This study aimed to establish globally relevant, agreed-upon standards for considering, conducting, publishing, and implementing LES in health care.

A modified Delphi consensus process was conducted. Potential participants were identified through a prior survey, workshop, and targeted outreach based on expertise and representation across global organizations producing or supporting LES. Three modified Delphi rounds were administered using JISC Online Surveys between January and April 2025. Participants rated 23 statements on a five-point Likert scale. Consensus was defined as ≥80% agreement (‘agree’ or ‘strongly agree’) with ≥85% panel response rate required per round. Qualitative feedback guided iterative statement revision. Draft statements were informed by an overview of living systematic reviews, a living evidence survey plus workshop activity, and an ongoing living critical interpretive synthesis of LES. Statements expanded upon the living methodology reporting guidance published by the PRISMA-LSR group to include other considerations for LES.

The Delphi panel comprised 29 experts from around the world, with 27 (93%) completing round 1, 26 (90%) round 2, and 27 (93%) completing round 3; 19 of 23 statements achieved consensus. Statements described conduct (n=12), including set up and maintenance of living mode as well as funding and resources; reporting (n=2); publishing (n=4); and implementation/appraisal (n=1). Final statements included ways to enable the living mode, such as version history; authoring tools; collaboration; unit of update; transparency; communication; publication considerations; and digital and technological considerations.

This study presents the first established consensus for best practices in considering, conducting, publishing, and implementing LES in health care. These LES standards can help align global processes, improve transparency, and promote sustainability. But there is still more to be done to accomplish these objectives, requiring that groups collaborate to embrace digital tools, adopt interoperability standards, and create effective appraisal tools. Competing Interest Statement MMG has performed paid consultancy work on living evidence syntheses outside of the submitted work for EBQ Consulting, LLC, and owns stock options in Dr.Evidence, an evidence-based insights software platform. DN was a member of the Royal College of General Practitioners (RCGP) steering committee to support the new Physical Activity and Lifestyle clinical priority. He has received funding for research from the NHS National Institute for Health Research School for Primary Care Research (NIHR SPCR) and the RCGP for independent research projects related to physical activity and dietary interventions. ZM is funded by an NHMRC investigator grant 1195676. GG, RH, MM, GR, JT, POV, and JLB have no conflicts or funding to disclose. The views expressed are those of the authors and do not necessarily represent those of the NHS, the NIHR, or the RCGP. Clinical Protocols Funding Statement This research received no specific grant from any funding agency in the public, commercial, or not-for-profit sectors. Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: Ethics committee of the University of Oxford gave ethical approval for this work (reference: OUDCE C1A 24 36). I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes Footnotes Removal of references to specific individuals in acknowledgments section until consent is obtained. Data Availability All data produced in the present work are contained in the manuscript.