Methodological quality of systematic reviews on interventions for osteoarthritis: a cross-sectional study

Healthcare providers need reliable evidence for supporting the adoption of new interventions, of which the source of evidence often originates from systematic reviews (SRs). However, little assessment on the rigor of SRs related to osteoarthritis interventions has been conducted. This cross-sectional study aimed to evaluate the methodological quality and predictors among SRs on osteoarthritis interventions.

Four electronic databases (Cochrane Database of Systematic Reviews, MEDLINE, Embase, and PsycINFO) were searched, from 1 January 2008 to 10 October 2019. An SR was eligible if it focused on osteoarthritis interventions, and we performed at least one meta-analysis. Methodological quality was assessed using the validated AMSTAR 2 instrument. Multivariate regression analyses were conducted to assess predictors of methodological quality.

In total, 167 SRs were included. The most SRs were non-Cochrane reviews (88.6%), and 54.5% investigated non-pharmacological interventions. Only seven (4.2%) had high methodological quality. Respectively, eight (4.8%), 25 (15.0%), and 127 (76.0%) SRs had moderate, low, and critically low quality. Main methodological weaknesses were as follows: only 16.8% registered protocol a priori, 4.2% searched literature comprehensively, 25.7% included lists of excluded studies with justifications, and 30.5% assessed risk of bias appropriately by considering allocation concealment, blinding of patients and assessors, random sequence generation and selective reported outcomes. Cochrane reviews [adjusted odds ratio (AOR) 251.5, 95% confidence interval (CI) 35.5-1782.6], being updates of previous SRs (AOR 3.9, 95% CI 1.1-13.7), and SRs published after 2017 (AOR 7.7, 95% CI 2.8-21.5) were positively related to higher methodological quality.

Despite signs of improvement in recent years, most of the SRs on osteoarthritis interventions have critically low methodological quality, especially among non-Cochrane reviews. Future SRs should be improved by conducting comprehensive literature search, justifying excluded studies, publishing a protocol, and assessing the risk of bias of included studies appropriately.