Figure 2.
Forest plot of leg pain severity after lumbar discectomy or conservative care. The mean difference and 95% confidence interval is plotted for each study. The pooled mean difference (diamond apex) and 95% confidence interval (diamond width) is calculated using a random effects model. Positive pooled mean difference suggests greater leg pain with lumbar discectomy. Negative pooled mean difference suggests less leg pain with lumbar discectomy. Mean difference −10, P < .001. Heterogeneity: I2 = 90%; P < .001.