Forest plots typically display the effect estimates for a specific outcome. They display the effect estimate and confidence interval for each study included in a meta-analysis, any inconsistency in those effect estimates, and the overall (average) effect estimate across the included studies. Usually, the results of individual studies are shown as squares centred on each study’s effect estimate. A horizontal line runs through each square to show each study’s confidence interval - usually, but not always, a 95% confidence interval. The overall effect estimate from the meta-analysis and its confidence interval are shown at the bottom, represented as a diamond. The centre of the diamond represents the pooled point estimate, and its horizontal tips represent the confidence interval.
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