Estimation of Physiologic Ability and Surgical Stress scoring system for predicting complications following abdominal surgery: A meta-analysis spanning 2004 to 2022

Table 2 Summary of subgroup analysis in comprehensive risk score and comparison with or without postoperative complications

Subgroup	Classification	Studies	MD (95%CI)	Subgroup I2	Subgroup effect (P value)	Subgroup overall I2
Sample size	< 100	3	0.51 (0.48-0.54)	95%	< 0.0001	99.6%
	100-200	4	0.12 (0.08-0.16)	0	< 0.0001
	≥ 200	4	0.14 (0.12-0.16)	85%	< 0.0001
Country	Japan	9	0.19 (0.04-0.34)	98%	0.01	0
	Non-Japan	3	0.18 (0.05-0.31)	88%	0.005
Influence factor	< 2.0	3	0.19 (0.09-0.28)	92%	< 0.0001	0
	≥ 2.0	9	0.19 (0.02-0.36)	98%	0.03
Surgical site	Gastrointestinal tract	6	0.13 (0.07-0.19)	57%	< 0.0001	0
	Hepatobiliary pancreas	5	0.24 (0.02-0.46)	99%	0.03
Age	Elderly	5	0.12 (0.08-0.15)	0%	< 0.0001	97.7%
	Non-elderly	7	0.25 (0.23-0.26)	99%	< 0.0001
CRS cut-off	< 0.5	7	0.20 (0.03-0.37)	98%	0.02	0
	≥ 0.5	5	0.14 (0.07-0.22)	55%	< 0.0001

CRS: Comprehensive risk score; MD: Mean difference; CI: Confidence interval.