Does transanal drainage tubes placement have an impact on the incidence of anastomotic leakage after rectal cancer surgery? a systematic review and meta-analysis

Table 3 Subgroup analyses of TDTs placement and anastomotic leakage after rectal cancer surgery risk

Group	Studies (n)	RR (95% CI)	P	Heterogeneity test
Group	Studies (n)	RR (95% CI)	P	P	I2 (%)
Total	7	0.89(0.57–1.37)	0.58	0.05	52
Design
Randomized controlled trials	4	0.84(0.49–1.45)	0.53	0.11	51
Non-randomized controlled trials	1	0.27(0.06–1.27)	0.10	NA	NA
Prospective Cohort study	2	1.26(0.70–2.27)	0.45	0.23	32
Area
Asia	5	0.68(0.47–1.00)	0.05	0.39	3
Europe	2	1.61(1.03–2.52)	0.04	0.85	0
Publication year
≤ 2015	3	0.64(0.21–1.96)	0.43	0.02	74
> 2015	4	1.08(0.75–1.53)	0.69	0.36	7
Quality score
≤ 7	3	0.89(0.38–2.08)	0.78	0.07	62
> 7	4	0.84(0.49–1.45)	0.53	0.11	51

ISSN: 1471-2407