Table 2. Discrete data: summary of this meta-analysis results.

Postoperative outcomes	studies	participants	statistical methods	effect size	test of heterogeneity	test of overall effect
Mortality	4	128	RR (random), 95% CI	0.20 [0.01, 3.85]	Not applicable	Z = 1.07 p = 0.29
Multiple complications	3	129	RR (random), 95% CI	0.34 [0.16, 0.71]	Chi-squared 0.72 df = 2 p = 0.70	Z = 2.85 p = 0.004
Sepsis	3	129	RR (random), 95% CI	0.43 [0.11, 1.64]	Chi-squared 0.62 df = 2 p = 0.73	Z = 1.23 p = 0.22
Respiratory complications	4	146	RR (random), 95% CI	0.23 [0.08, 0.65]	Chi-squared 0.74 df = 2 p = 0.69	Z = 2.78 p = 0.005
Hepatic failure	2	96	RR (random), 95% CI	0.39 [0.10, 1.57]	Chi-squared 0.01 df = 1 p = 0.92	Z = 1.33 p = 0.18
Renal failure	2	96	RR (random), 95% CI	0.81 [0.34, 1.92]	Chi-squared 0.34 df = 1 p = 0.56	Z = 0.47 p = 0.64
Anastomotic leakage	3	113	RR (random), 95% CI	0.35 [0.06, 2.21]	Chi-squared 0.23 df =1 p = 0.63	Z = 1.12 p = 0.26

RR = relative risk; CI = confidence interval; df = degrees of freedom.