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Updated: Aug 25, 2026

Comparing Bibliometric Analysis Using PubMed, Scopus, and Web of Science Databases
Published on: October 24, 2019
Empirical assessment of effect of publication bias on meta-analyses
A J Sutton1, S J Duval, R L Tweedie
1Department of Epidemiology and Public Health, University of Leicester, Leicester LE1 6TP.
Objective:
To assess the effect of publication bias on the results and conclusions of systematic reviews and meta-analyses.
Design:
Analysis of published meta-analyses by trim and fill method.
Studies:
48 reviews in Cochrane Database of Systematic Reviews that considered a binary endpoint and contained 10 or more individual studies.
Main Outcome Measures:
Number of reviews with missing studies and effect on conclusions of meta-analyses.
Results:
The trim and fill fixed effects analysis method estimated that 26 (54%) of reviews had missing studies and in 10 the number missing was significant. The corresponding figures with a random effects model were 23 (48%) and eight. In four cases, statistical inferences regarding the effect of the intervention were changed after the overall estimate for publication bias was adjusted for.
Conclusions:
Publication or related biases were common within the sample of meta-analyses assessed. In most cases these biases did not affect the conclusions. Nevertheless, researchers should check routinely whether conclusions of systematic reviews are robust to possible non-random selection mechanisms.
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