Background: despite wide usage of the PRISMA Statement reporting guideline by systematic review authors, compliance with its items regarding literature search reporting is suboptimal. Currently there is no universal, or consensus-driven guidance, on how to report search strategies.
Objectives: we sought to develop an international standard for literature search reporting aligned with the PRISMA Statement to improve the quality and reproducibility of reported literature searches.
Methods: we formed an executive committee to lead the PRISMA-S extension development. The study protocol was published prior to study inception. To identify potential items for inclusion, we performed a literature search. Identified items were reviewed for overlap and consolidated. We then used a three-step Delphi survey process to assess the items. The first survey asked 163 international experts to rate each item, and the second and third rounds asked respondents to select the 25 most necessary items for a checklist. Potential items moved to rounds 2 and 3 based on prespecified criteria. Remaining items were discussed at an in-person consensus conference. After the consensus conference, the remaining items were consolidated into a checklist. Executive committee members developed an accompanying explanation and elaboration document. The checklist and documentation were distributed for pilot testing.
Results: we identified 405 potential items from 61 sources located through the literature search process. Sources included both explicit reporting guidelines and studies assessing reproducibility of search strategies. These were consolidated into 123 potential items for the Delphi survey. We received 52 responses (32% response rate) to the first survey, and 35 (67% response rate) to both surveys two and three. The results of the Delphi process were reported at the consensus conference meeting in May 2016. Post-consensus conference, 34 items remained. The checklist was finalised into nine items and 17 subitems. Pilot testing is underway.
Conclusions: the PRISMA-S extension for the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) reporting guideline will provide a consensus-driven international standard for literature search reporting. Using this new reporting guideline may enable librarians and information specialists to produce higher-quality, more reproducible, transparent search strategies for systematic reviews and other literature review-based publications.
Patient or healthcare consumer involvement: we hope this guideline will empower all readers, especially patients and healthcare consumers, to understand the information retrieval methods behind these studies, the reasoning behind the why, how, and where the search strategy is conducted.