Methodological and reporting quality of search strategies of systematic reviews evaluating the therapeutic use of cannabis derivatives and their synthetic analogues. Meta-epidemiological study

Session Type
Communicating evidence including misinformation and research transparency
Rocha GFA1, Sá KMM2, Latorraca COC3, Pacheco RL3, Martimbianco ALC4, Riera R5
1Universidade Federal de São Paulo, Brazil
2Universidade Metropolitana de Santos, Brazil
3Centro Universitário São Camilo / Hospital Sírio-Libanês, Brazil
4Universidade Metropolitana de Santos / Hospital Sírio-Libanês, Brazil
5Universidade Federal de São Paulo / Hospital Sírio-Libanês, Brazil

Background: an increasing number of systematic reviews (SRs) have been conducted to map, synthesize, and critically evaluate clinical trials on the effects of cannabis derivatives and their synthetic analogues for different health conditions. The process of searching for studies impacts the reliability of the SRs. It is important to understand how this process has been conducted to guide the planning of SRs and to support further strategies for continuous enhancement of methodological recommendations.
Objectives: to assess the methodological and reporting quality of search strategies used by SRs to identify randomized clinical trials about therapeutical use of cannabis derivatives and their synthetic analogues.
Methods: meta-epidemiological study conducted in the Discipline of Evidence-Based Medicine, Escola Paulista de Medicina, Unifesp, Brazil and supported by Conselho Nacional de Desenvolvimento Científico e Tecnológico through an academic scholarship (CNPq, number 134763/2021-1). Two authors independently investigated the use of PRESS and PRISMA-S checklists by SRs included and additionally the adequacy to AMSTAR-2 item related do search process (item 4).
Results: we identified 86 SRs on the topic, published in MEDLINE from January 1, 2019 to September 21, 2021. None of them referred the use of PRESS for constructing the searches, nor PRISMA-S checklist for reporting them. About the AMSTAR-2 item 4, 89.53% (n=77) SRs searched on at least 2 relevant databases, 32.56% (n=28) used MESH terms properly, all respected a limit of 1 year between the search date and the SR publication, but only 1,1% (n=1) SR presented a justification for the use of filters and limits.
Conclusions: PRESS and PRISMA-S checklists have been poorly adopted by SRs on the cannabis therapy field. Some of the components of AMSTAR-2 item 4 are not fully covered as well.
Patient, public and/or healthcare consumer involvement: by revealing the low adherence to methodological and reporting tools, this study alerts us to the risk of bias in the process of conducting and reporting the clinical effects of cannabinoids, which may limit the applicability of its conclusions or even mislead the body of evidence supporting decision making.