Systematic reviews and meta-analyses of preclinical studies: even if their inner methodology is acceptable, the quality of the included preclinical studies limits the validity of their results.
Systematic reviews and meta-analyses have been proposed to synthesize the literature and counteract the lack of power of preclinical studies, which are often performed on small sample sizes. In this methodological review, we sought to assess the methodological quality of these reviews and of the included studies, and then studied by a meta-epidemiological analysis whether methodological characteristics of the included studies were associated with effect size. Our study included a sample of 212 systematic reviews with meta-analyses of preclinical studies published from January 2018 to March 2020. The methodological quality of these reviews was acceptable compared with previous assessments, but the quality of the included preclinical studies remained poor, limiting the validity of the reviews. In the meta-epidemiological analysis, none of the methodological characteristics of the included studies were associated with the effect size.
This work was published in Scientific Reports (https://doi.org/10.1038/s41598-022-24447-4).