Enhanced recovery after surgery in gastric cancer surgery: Systematic review and meta-analysis of perioperative indwelling drainage tube use

Table 4 Summary of Grading of Recommendations Assessment, Development and Evaluation evidence

Certainty assessment					Number of patients		Effect
Outcome	n	Study design	Risk of bias	Inconsistency	Indirectness	Imprecision	Other considerations	Intervention	Control	Relative (95%CI)	Absolute (95%CI)	Certainty	Importance
Time to first flatus (hour)	7	Randomized trials	Not serious	Not serious	Not serious	Not serious	None	345	343	-	MD = 10.24 Lower (12.69 Lower, 7.79 Lower)	++++ high	Critical
Time to first flatus (day)	9	Randomized trials	Not serious	Not serious	Not serious	Not serious	None	322	322	-	MD = 1.09 SD: Lower (1.36 Lower, 0.83 Lower)	++++ high	Critical
Time to oral intake (hour)	3	Randomized trials	Not serious	Not serious	Not serious	Not serious	None	190	189	-	MD = 21.06 Lower (23.18 Lower, 18.94 Lower)	++++ high	Critical
Time to oral intake (day)	2	Randomized trials	Not serious	Not serious	Not serious	Not serious	None	61	52	-	MD = 0.56 Lower (0.92 Lower, 0.2 Lower)	++++ high	Critical
Time to first ambulation (day)	2	Randomized trials	Not serious	Not serious	Not serious	Not serious	None	97	91	-	SMD = 0.45 SD: Lower (0.74 Lower, 0.16 Lower)	++++ high	Critical
Length of hospital stay	15	Randomized trials	Not serious	Not serious	Not serious	Not serious	None	580	579	-	MD = 2.92 Lower (3.15 Lower, 2.68 Lower)	++++ high	Important
Hospitalization cost	7	Randomized trials	Not serious	Not serious	Serious a	Not serious	None	258	259	-	SMD = 0.72 SD: Lower (0.9 Lower, 0.54 Lower)	+++-moderate a	Important
Nasogastric tube removal time (day)	3	Randomized trials	Not serious	Not serious	Not serious	Not serious	None	89	89	-	MD = 1.7 Lower (1.96 Lower, 1.44 Lower)	++++ high	Critical
Urinary catheter removal time (hour)	2	Randomized trials	Not serious	Not serious	Serious b	Not serious	None	103	103	-	SMD = 4.52 SD: Lower (5.57 Lower, 3.48 Lower)	+++-moderate a	Critical
Urinary catheter removal time (day)	2	Randomized trials	Not serious	Not serious	Not serious	Not serious	None	60	60	-	SMD = 2.33 SD: Lower (2.8 Lower, 1.86 Lower)	++++ high	Critical
Abdominal drain removal time	4	Randomized trials	Not serious	Not serious	Not serious	Not serious	None	178	177	-	SMD = 0.91 SD: Lower (1.13 Lower, 0.69 Lower)	++++ high	Critical
Total complication rate	16	Randomized trials	Not serious	Not serious	Not serious	Not serious	None	88/699 (12.6%)	173/697 (24.8%)	OR = 0.41 (0.30-0.55)	129 fewer per 1000 (from 158 fewer to 95 fewer)	++++ high	Critical
Incidence of intestinal obstruction	12	Randomized trials	Not serious	Not serious	Not serious	Not serious	None	13/473 (2.7%)	16/479 (3.3%)	OR = 0.83 (0.41-1.71)	6 fewer per 1000 (from 19 fewer to 22 more)	++++ high	Critical
Incidence of nausea and vomiting	6	Randomized trials	Not serious	Not serious	Not serious	Not serious	None	16/206 (7.8%)	15/206 (7.3%)	OR = 1.07 (0.52-2.20)	5 more per 1000 (from 34 fewer to 75 more)	++++ high	Important
Incidence of anastomotic leakage	12	Randomized trials	Not serious	Not serious	Not serious	Not serious	None	6/508 (1.2%)	17/499 (3.4%)	OR = 0.37 (0.15-0.89)	21 fewer per 1000 (from 29 fewer to 4 fewer)	++++ high	Critical
Incidence of surgical site infection	13	Randomized trials	Not serious	Not serious	Not serious	Not serious	None	10/506 (2.0%)	18/502 (3.6%)	OR = 0.56 (0.27-1.18)	15 fewer per 1000 (from 26 fewer to 6 more)	++++ high	Critical
Incidence of urinary tract infection	8	Randomized trials	Not serious	Not serious	Not serious	Not serious	None	3/317 (0.9%)	11/315 (3.5%)	OR = 0.39 (0.14-1.06)	21 fewer per 1000 (from 30 fewer to 2 more)	++++ high	Important
Incidence of pulmonary infection	9	Randomized trials	Not serious	Not serious	Not serious	Not serious	None	8/380 (2.1%)	21/372 (5.6%)	OR = 0.38 (0.17-0.83)	34 fewer per 1000 (from 46 fewer to 9 fewer)	++++ high	Important

Unit conversion may lead to heterogeneity among studies; few patients and observed events included in the study/does not meet optimal information size/95% confidence interval too wide. CI: Confidence interval; MD: Mean difference; OR: Odds ratio; SMD: Standardized mean difference; +: Grading of Recommendations Assessment, Development and Evaluation quality rating symbol; ++++: High certainty; +++-: Moderate certainty.