Meta-analysis - interpretation of forest plots: A wood for the trees.

Abstract

A forest plot is a graphical tool to visualise and interpret the summary of estimated results in a meta-analysis. However, it is limited by its inability to control for random error, publication bias, heterogeneity, and confounding factors. Therefore, the interpretation can be misleading, resulting in flawed conclusions. A careful interpretation and other complementing techniques are necessary to comprehensively summarise evidence in meta-analyses, reducing the risk of erroneous conclusions. The present review explores the components of forest plots, how to interpret them correctly, fundamental limitations, and techniques to mitigate them, along with examples to provide practical insights to ensure more accurate and reliable meta-analytic results.