Fig. 2From: Postoperative pain after different doses of remifentanil infusion during anaesthesia: a meta-analysisForest plot for comparison of pain scores at 1-2 h (A), 3-8 h (B), 24 h (C), and 48 h (D). Data were pooled using a random-effects model to calculate the WMD and 95% CI for each outcome. CI indicates confidence interval; df, degrees of freedom; M-H, Mantel-Haenszel; WMD, weighted mean differencesBack to article page