The magnitude of small-study effects in the Cochrane Database of Systematic Reviews: an empirical study of nearly 30 000 meta-analyses

Ref ID 520
First Author L. Lin
Journal BMJ EVIDENCE-BASED MEDICINE
Year Of Publishing 2020
URL https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6942244/pdf/nihms-1038392.pdf
Keywords Cochrane
Statistical
Publication bias
General medical
Problem(s) Poor consideration of publication bias
Number of systematic reviews included 3302
Summary of Findings The regression intercepts and skewness indicated substantial "small-study effects" (publication bias) in around 30% to 35% meta-analyses, and considerable small-study effects in around 20% to 40% of meta-analyses. The trim and fill methods (PTF and RTF) implied substantial and considerable small-study effects in less meta-analyses than the other measures.
Did the article find that the problem(s) led to qualitative changes in interpretation of the results? Not Applicable
Are the methods of the article described in enough detail to replicate the study? No