Publication bias

Publication bias describes the phenomenon where the decision to publish research findings is influenced by the nature and statistical significance of the results. Studies with statistically significant or positive outcomes are more likely to be published than those with non-significant or negative results. This selective publication of research can lead to an overestimation of an intervention’s true effectiveness when syntheses are based solely on published literature. Potential publication bias in a meta-analysis is commonly assessed using Egger’s test and funnel plot asymmetry. If publication bias is identified sensitivity analyses can be used to explore correction methods.