Why Make a Forest plot: Forest plots take all the relevant studies asking the same questions, identify a common statistic, and displays them on a single axis, allowing on to compare multiple papers in a single image.
Horizontal Axis: usually represents the statistic
Vertical Axis: “line of null effect” (no difference between two interventions)
Black Box: point estimate of the study result and representation of study size (bigger box=more
Horizontal Line: represents the 95% confidence intervals of the study. Any study line that crosses the
line of null effect does not show a statistically significant result.
Diamond: result when all the studies are combined together and averaged
Heterogeneity: how consistent the studies are, if the I2 value is >50% it might mean the studies are inconsistent due to a reason other than chance.