Forest plot for comparison of pain scores at 24 hours post-op. The table displays the study with reference number in parenthesis, mean, standard deviation, sample size, difference in means with 95% confidence interval, heterogeneity, overall effect, and p-value. The Forest plot displays point estimate and 95% confidence interval, CI = confidence interval, PCA = patient-controlled analgesia, PCEA = patient-controlled epidural analgesia, SD = standard deviation.