Table 3.

GRADE Evidence Profile

Quality assessment							No. of patients		Relative Effect (95% CI)	Quality
No. of studies	Design	Risk of bias	Inconsistency	Indirectness	Imprecision	Other considerations	Elevated HbA1c	Normal HbA1c
Major postoperative complications
9	Observational studies	Moderate	-	-	-	-	586	1024	OR 2.16 (1.54, 3.01)	⊕⊕⊕⊖
										Moderate
Overall postoperative complications
12	Observational studies	Moderate	-	-	-	Large effect size	10063	15030	OR 2.12 (1.48, 3.04)	⊕⊕⊕⊖
										Moderate
Anastomotic leak
6	Observational studies	Moderate	-	-	-	-	339	608	OR 2.80 (1.63, 4.83)	⊕⊕⊖⊖
										Low
Overall infections
6	Observational studies	Moderate	-	-	Serious		9082	13024	OR 1.69 (1.05, 2.71)	⊕⊕⊖⊖
										Low
Wound infections
3	Observational studies	Moderate	-	-	Serious		8920	12859	OR 1.21 (1.08, 1.36)	⊕⊕⊖⊖
										Low
Pneumonia
4	Observational studies	Moderate	Serious	-	Serious	-	8935	12888	OR 0.77 (0.61, 0.97)	⊕⊕⊖⊖
										Low

OR: odds ratio.