Fig. 1. 95% CI = 95% confidence interval. Positive effects indicate that pain perception thresholds are greater in depressed subjects, ie, depressed subjects are less sensitive to experimental pain stimuli. Negative effects indicate that depressed subjects have lower pain perception thresholds. Each rectangle represents one of the studies included in the meta-analysis; the line in the center of the rectangle represents the effect size, the size of the central diamond represents the sample size, and the right and left extremes of the rectangles represent the 95% confidence intervals.