Comparison 2. Stratified by method of cholecystectomy.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Mortality	5	662	Risk Ratio (M‐H, Fixed, 95% CI)	1.70 [1.10, 2.64]
1.1 Open cholecystectomy & common bile duct exploration	3	383	Risk Ratio (M‐H, Fixed, 95% CI)	1.86 [1.03, 3.35]
1.2 Laparoscopic cholecystectomy after sphincterotomy	2	279	Risk Ratio (M‐H, Fixed, 95% CI)	1.53 [0.79, 2.94]
2 Biliary pain or cholecystitis	5	654	Risk Ratio (M‐H, Fixed, 95% CI)	14.56 [4.95, 42.78]
2.1 Open cholecystectomy & common bile duct exploration	3	375	Risk Ratio (M‐H, Fixed, 95% CI)	11.09 [2.69, 45.79]
2.2 Laparoscopic cholecystectomy after spincterotomy	2	279	Risk Ratio (M‐H, Fixed, 95% CI)	18.84 [3.66, 97.00]
3 Pancreatitis	5	662	Risk Ratio (M‐H, Fixed, 95% CI)	2.11 [0.39, 11.43]
3.1 Open cholecystectomy & common bile duct exploration	3	383	Risk Ratio (M‐H, Fixed, 95% CI)	2.11 [0.39, 11.43]
3.2 Laparoscopic cholecystectomy after sphincterotomy	2	279	Risk Ratio (M‐H, Fixed, 95% CI)	0.0 [0.0, 0.0]
4 Recurrent jaundice or cholangitis	5	662	Risk Ratio (M‐H, Fixed, 95% CI)	2.53 [1.09, 5.87]
4.1 Open cholecystectomy & common bile duct exploration	3	383	Risk Ratio (M‐H, Fixed, 95% CI)	3.04 [0.47, 19.49]
4.2 Laparoscopic cholecystectomy after sphincterotomy	2	279	Risk Ratio (M‐H, Fixed, 95% CI)	2.41 [0.94, 6.18]
5 Major adverse events	5	662	Risk Ratio (M‐H, Fixed, 95% CI)	0.60 [0.35, 1.02]
5.1 Open cholecystectomy & common bile duct exploration	3	383	Risk Ratio (M‐H, Fixed, 95% CI)	0.73 [0.35, 1.53]
5.2 Laparoscopic cholecystectomy after sphincterotomy	2	279	Risk Ratio (M‐H, Fixed, 95% CI)	0.47 [0.21, 1.04]
6 Minor adverse events	5	662	Risk Ratio (M‐H, Fixed, 95% CI)	0.45 [0.22, 0.91]
6.1 Open cholecystectomy & common bile duct exploration	3	383	Risk Ratio (M‐H, Fixed, 95% CI)	0.28 [0.11, 0.73]
6.2 Laparoscopic cholecystectomy after sphincterotomy	2	279	Risk Ratio (M‐H, Fixed, 95% CI)	1.03 [0.32, 3.27]
7 Additional cholangiography (ERCP or PTC)	5	662	Risk Ratio (M‐H, Fixed, 95% CI)	2.36 [1.29, 4.32]
7.1 Open cholecystectomy & common bile duct exploration	3	383	Risk Ratio (M‐H, Fixed, 95% CI)	0.93 [0.45, 1.94]
7.2 Laparoscopic cholecystectomy after sphincterotomy	2	279	Risk Ratio (M‐H, Fixed, 95% CI)	20.40 [2.82, 147.51]
8 Difficult cholecystectomy	5	654	Risk Ratio (M‐H, Fixed, 95% CI)	0.68 [0.39, 1.17]
8.1 Open cholecystectomy & common bile duct exploration	3	375	Risk Ratio (M‐H, Fixed, 95% CI)	3.38 [0.14, 80.52]
8.2 Laparoscopic cholecystectomy after sphincterotomy	2	279	Risk Ratio (M‐H, Fixed, 95% CI)	0.63 [0.36, 1.10]