Impact of frailty on short-term postoperative outcomes in patients undergoing colorectal cancer surgery: A systematic review and meta-analysis

Table 2 Findings of the subgroup analysis

	Mortality (30-d)	Mortality (90-d)	Mortality (1-yr)	Any complications	Major complications
	RR (95%CI) (n; I2)
Study design
Retrospective	1.85 (1.37, 2.50) (7; 57.1%)1	3.96 (0.54, 28.8) (2; 94.1%)	8.80 (6.84, 11.3) (4; 0.0%)1	2.02 (1.64, 2.49) (9; 89.9%)1	2.38 (0.93, 6.07) (4; 94.6%)
Prospective	3.94 (1.30, 12.0) (4; 19.7%)1	5.03 (1.38, 18.3) (3; 38.9%)1	1.88 (1.03, 3.41) (2; 6.1%)1	1.54 (1.33, 1.78) (6; 17.5%)1	3.23 (2.11, 4.95) (5; 32.7%)1
Tumor stage
Stage 0 to 22	3.54 (1.79, 7.02) (6; 0.0%)1	4.07 (1.14, 14.6) (4; 86.8%)1	4.29 (1.83, 10.1) (4; 87.0%)1	1.67 (1.42, 1.97) (9; 42.4%)1	2.57 (1.41, 4.66) (5; 64.7%)1
Type of surgery3
Minimal invasive	3.10 (1.33, 7.22) (5; 0.0%)1	4.61 (0.85, 25.1) (3; 65.3%)	18.8 (5.22, 67.7) (2; 0.0%)1	2.02 (1.59, 2.57) (8; 58.0%)1	3.12 (1.71, 5.68) (5; 60.2%)1
Open	1.63 (1.01, 2.63) (4; 78.7%)1	2.14 (0.71, 6.43) (1; -)	1.88 (1.03, 3.41) (2; 6.1%)1	1.51 (1.27, 1.81) (4; 60.8%)1	1.80 (1.09, 2.98) (3; 68.5%)1

¹Statistically significant at P < 0.05.

²Not all studies reported on the stage of the tumor. Furthermore, we have done this as a sensitivity analysis after excluding studies with subjects having tumor stage of 3 or more (only two studies had subjects with stage ≥ 3).

³Not all studies reported on the type of surgery.

RR: Relative risk; CI: Confidence interval.