Preventive drainage and anastomotic leakage after colorectal surgery

Figure 1  Flow diagram of included studies.

Figure 2 Meta-analysis results from 38 studies in 36 papers. In the random effects model, risk ratio (RR) = 0.67, 95%CI: 0.54-0.83; P = 0.0002.

Figure 3 Subgroup analyses of drainage models and anastomotic leakage after colorectal surgery risk. CI: Confidence interval; RR: Risk ratio.

Figure 4 Sensitivity analyses were performed to investigate potential sources of heterogeneity and showed the main result was robust. CI: Confidence interval; RR: Risk ratio.

Figure 5 Funnel plot and Begg test plot. A: The funnel plot on the anastomotic leakage; B: Begg test and Begg test plot were performed to confirm that there was no significant publication bias between the drain and the occurrence of anastomotic leakage after colorectal surgery, P = 0.0576.