Extension of the PRISMA 2020 statement for living systematic reviews (PRISMA-LSR): checklist and explanation

Publications of living systematic reviews (LSRs) are increasing rapidly. Guidance facilitating transparent, complete, and accurate reporting of LSRs is needed. This paper reports the development of an extension of the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) 2020 statement for LSRs (PRISMA-LSR). The PRISMA-LSR extension includes the PRISMA-LSR checklist, the PRISMA-LSR flow diagram, reporting recommendations for the LSR status, and an explanation and elaboration document. This extension has been developed as an “add-on” to the PRISMA 2020 statement, meaning it should be used in addition to the PRISMA 2020 statement. The PRISMA-LSR extension is expected to benefit authors, editors, peer reviewers, and users of LSRs through transparent, complete, and accurate reporting of LSRs. Living systematic reviews (LSRs) are attracting attention from researchers and medical journals.12 Between 2014 (when the LSR approach first emerged3) and 2019, the rate of publication of these systematic reviews was low; however, since 2019, there has been a rapid increase. Indeed, the total number of LSRs published in 2020 and 2021 exceeded the total number published before 2020.4 LSRs are characterised by a continual search of the literature so that new evidence can be incorporated soon after it becomes available.35 These reviews are particularly important when research is published rapidly and where concomitant policy decisions are required, such as during the covid-19 pandemic.678 The Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) 2020 statement is intended to facilitate transparent, complete, and accurate reporting of systematic reviews.9101112 The PRISMA 2020 statement was designed primarily to provide guidance for systematic reviews of studies that evaluate the effects of interventions. While the statement was intended for original, updated, or living systematic reviews, the developers noted that there might be additional reporting considerations that …