Epidemiology, methodological quality, and reporting characteristics of systematic reviews and meta-analyses on coronavirus disease 2019: A cross-sectional study

During the coronavirus disease 2019 (COVID-19) pandemic, convenient accessibility and rapid publication of studies related to the ongoing pandemic prompted shorter preparation time for studies. Whether the methodological quality and reporting characteristics of published systematic reviews (SRs)/meta-analyses are affected during the specific pandemic condition is yet to be clarified. This study aimed to evaluate the epidemiology, methodological quality, and reporting characteristics of published SRs/meta-analyses related to COVID-19. The Ovid Medline, Ovid Embase, Cochrane Library, and Web of Science electronic databases were searched to identify published SRs/meta-analyses related to the COVID-19 pandemic. Study screening, data extraction, and methodology quality assessment were performed independently by 2 authors. The methodology quality of included SRs/meta-analyses was evaluated using revised version of a measurement tool to assess SRs, and the reporting characteristics were assessed based on the preferred reporting items for SRs and meta-analyses guidelines. A total of 47 SRs/meta-analyses were included with a low to critically low methodological quality. The median number of days from the date of literature retrieval to the date that the study was first available online was 21 days; due to the limited time, only 7 studies had study protocols, and the studies focused on a wide range of COVID-19 topics. The rate of compliance to the preferred reporting items for SRs and meta-analyses checklists of reporting characteristics ranged from 14.9% to 100%. The rate of compliance to the items of protocol and registration, detailed search strategy, and assessment of publication bias was less than 50%. SRs/meta-analyses on COVID-19 were poorly conducted and reported, and thus, need to be substantially improved.