The Proliferation of Living Systematic Reviews (LSRS) - Dead on Arrival? A Review of LSR Methodology

ABSTRACT

Objectives: Living systematic reviews (LSRs) maintain the relevance of systematic reviews through regular, continuous updates. This research aimed to assess if all LSRs are equal and to identify areas of methodological confusion to provide clarity for those undertaking an LSR. Method(s) A scoping exercise was conducted, informed by pragmatic searches of MEDLINE, Embase and Epistemonikos, to identify records explicitly referring to LSRs. No date limits were applied. Study selection was conducted by double independent reviewers. Where a preprint LSR was superseded by a peer-reviewed publication, the preprint record was excluded. A single reviewer conducted brief data extraction. A narrative synthesis was conducted. Result(s) 760 records were screened at title and , and 241 were assessed for eligibility at full text. 141 LSRs (either full LSR or protocol only) were extracted and synthesised. 97 LSRs focussed on COVID-19, and 44 were non-COVID-19 related. 29 were Cochrane LSRs. Of the 112 non-Cochrane LSRs, 77 were registered on PROSPERO. There appears to be some confusion amongst reviewers regarding PROSPERO's acceptance of LSRs. Justification for the use of LSR methodology and a description of how this methodology would be followed was not always reported. 40 reviews did not describe a clear schedule for search updates or stated that updates would only be conducted if new evidence became available;these may more accurately be described as standard review updates. 32 reviews did not report updates at the purported schedule (whilst not reporting that the review had been officially terminated). Thus, many "living" reviews are effectively dead on arrival. Very few authors reported under what circumstances the LSR would cease. Conclusion(s) LSRs present an opportunity to ensure that a body of evidence is kept up to date. However, caution is advised regarding jumping on a methodological bandwagon without sufficient understanding of the methods and funding required. Copyright © 2022