FIGURE 2. Meta-analysis of RCTs comparing prophylactic drain versus no drain after colorectal resection. Estimates of drain effects of each study are presented on a log scale along with the 95% CI. The weight of each study is reflected by the size of square. Studies were analyzed according to the complication end points clinical leakage (A), wound infections (B), and pulmonary complications (C). The open diamond represents the global estimate of the drain effect along with the 95% CI (random-effects model). Test of heterogeneity is provided by χ²-based Q statistic.