Publication Bias

Publication bias is the tendency for academic journals to prioritize publishing significant results over equally well-conducted studies that yield non-significant or null results. Researchers are aware of publication bias and often respond by preferring to submit papers with positive results, perpetuating this bias as journal editors and reviewers are less exposed to papers with negative or null findings. Meta-analysis can help to uncover publication bias within a research literature because it outputs indicators of publication bias, including funnel plots, and statistical tests such as Egger’s regression test and Duval and Tweedie’s trim and fill method. This chapter will cover the indicators of publication bias to introduce their use in reporting results following a meta-analysis.