The methodological quality of COVID-19 systematic reviews is low, except for Cochrane reviews: a meta-epidemiological study

KATAOKA, Y.; Oide, S.; Ariie, T.; Tsujimoto, Y.; Furukawa, T. A.

Objectives: The objective of this study was to investigate the methodological quality of COVID-19 systematic reviews (SRs) indexed in medRxiv and PubMed, compared with Cochrane COVID Reviews. Study Design and Setting: This is a cross-sectional meta-epidemiological study. We searched medRxiv, PubMed, and Cochrane Database of Systematic Reviews for SRs of COVID-19. We evaluated the methodological quality using A MeaSurement Tool to Assess systematic Reviews (AMSTAR) checklists. The maximum AMSTAR score is 11, and minimum is 0. Higher score means better quality. Results: We included 9 Cochrane reviews as well as randomly selected 100 non-Cochrane reviews in medRxiv and PubMed. Compared with Cochrane reviews (mean 9.33, standard deviation 1.32), the mean AMSTAR scores of the articles in medRxiv were lower (mean difference -2.85, 95%confidence intervals (CI): -0.96 to -4.74) and those in PubMed was also lower (mean difference -3.28, 95% CI: -1.40 to -5.15), with no difference between the latter two. Conclusions: It should be noted that AMSTAR is not a perfect tool of assessing quality SRs other than intervention. Readers should pay attention to the potentially low methodological quality of COVID-19 SRs in both PubMed and medRxiv but less so in Cochrane COVID reviews.