Editorial policies and experiences with PRISMA-P 2015: a cross-sectional study

Objective: To explore editorial policies and experiences with the Preferred Reporting Items for Systematic review and Meta-Analysis Protocols (PRISMA-P) 2015 reporting guideline.Methods: Through a PubMed search, we identified the 25 journals that had published the highest number of systematic review protocols from May 2021 to May 2024. From corresponding journal websites, two authors independently extracted general and PRISMA-P specific reporting instructions and journal policies on publishing systematic review protocols. We distinguished between mandatory, non-mandatory, and generic terminology. We applied thematic content analysis to the extracted data. We emailed five editorial offices and 15 journal editors with invitations to participate in interviews on their experiences with PRISMA-P 2015. The interviews were conducted using a semi-structured interview guide around three prespecified themes: level of experience with publishing review protocols, views on using PRISMA-P 2015 in the editorial process, and reflections on its strengths and challenges. Framework analysis was applied to the interview transcripts.Results: From the 25 journals, we identified 143 descriptions of reporting instructions and journal policies. Sixty-two (43%, from 21 journals) were general reporting instructions, 27 (19%, from 11 journals) were PRISMA-P 2015 specific reporting instructions, and 54 (38%, from 19 journals) were journal policies on publishing systematic review protocols. Most (24 of 27, 89%) of the PRISMA-P 2015 reporting instructions were on use or endorsement (e.g., that authors were required or strongly encouraged to follow PRISMA-P 2015) or on requirements to submit a completed PRISMA-P 2015 checklist, frequently expressed using mandatory terminology. Ten journal editors were interviewed and several suggestions for modifying PRISMA-P 2015 emerged. Some suggestions related to the reporting guideline in general (e.g., add explanation on the distinction between registry entries and full protocols). Other suggestions related to adding or modifying content (e.g., report the current stage of the review or integrate guidance from other sources, such as PRISMA-Search).Conclusion: While nearly all of the 25 included journals had general reporting instructions and policies for publishing systematic review protocols, around half provided specific PRISMA-P 2015 reporting instructions. The interviewed journal editors suggested several additions and modifications to PRISMA-P 2015. Our findings provide context for editors, peer reviewers, authors, and other users of PRISMA-P 2015 and will inform the forthcoming update of the reporting guideline.