Comparison 1. Open surgery versus ERCP.

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Mortality	8	729	Odds Ratio (M‐H, Fixed, 95% CI)	0.51 [0.18, 1.44]
1.1 Randomisation once bile duct stones proven	4	275	Odds Ratio (M‐H, Fixed, 95% CI)	0.39 [0.06, 2.72]
1.2 Randomisation on suspicion of bile duct stones	3	356	Odds Ratio (M‐H, Fixed, 95% CI)	0.48 [0.09, 2.65]
1.3 High‐risk participants only	1	98	Odds Ratio (M‐H, Fixed, 95% CI)	0.68 [0.11, 4.27]
2 Mortality (Sensitivity analysis)	8		Odds Ratio (M‐H, Fixed, 95% CI)	Subtotals only
2.1 Good‐outcome analysis	8	737	Odds Ratio (M‐H, Fixed, 95% CI)	0.50 [0.18, 1.42]
2.2 Poor‐outcome analysis	8	737	Odds Ratio (M‐H, Fixed, 95% CI)	1.00 [0.43, 2.32]
2.3 Best‐case for open surgery	8	737	Odds Ratio (M‐H, Fixed, 95% CI)	0.46 [0.17, 1.25]
2.4 Worst‐case for open surgery	8	737	Odds Ratio (M‐H, Fixed, 95% CI)	1.10 [0.47, 2.55]
3 Total morbidity	8	729	Odds Ratio (M‐H, Fixed, 95% CI)	1.12 [0.77, 1.62]
3.1 Randomisation once bile duct stones proven	4	275	Odds Ratio (M‐H, Fixed, 95% CI)	1.02 [0.59, 1.77]
3.2 Randomisation on suspicion of bile duct stones	3	356	Odds Ratio (M‐H, Fixed, 95% CI)	1.11 [0.63, 1.96]
3.3 High‐risk participants only	1	98	Odds Ratio (M‐H, Fixed, 95% CI)	1.56 [0.57, 4.30]
4 Morbidity (Sensitivity analysis)	8		Odds Ratio (M‐H, Fixed, 95% CI)	Subtotals only
4.1 Good‐outcome analysis	8	737	Odds Ratio (M‐H, Fixed, 95% CI)	1.09 [0.76, 1.58]
4.2 Poor‐outcome analysis	8	737	Odds Ratio (M‐H, Fixed, 95% CI)	1.19 [0.83, 1.71]
4.3 Best‐case for open surgery	8	737	Odds Ratio (M‐H, Fixed, 95% CI)	1.07 [0.74, 1.54]
4.4 Worst‐case for open surgery	8	737	Odds Ratio (M‐H, Fixed, 95% CI)	1.22 [0.84, 1.75]
5 Retained stones	7	609	Odds Ratio (M‐H, Fixed, 95% CI)	0.36 [0.21, 0.62]
5.1 Randomisation once bile duct stones proven	4	275	Odds Ratio (M‐H, Fixed, 95% CI)	0.35 [0.17, 0.72]
5.2 Randomisation on suspicion of bile duct stones	2	236	Odds Ratio (M‐H, Fixed, 95% CI)	0.30 [0.12, 0.74]
5.3 High‐risk participants only	1	98	Odds Ratio (M‐H, Fixed, 95% CI)	3.19 [0.13, 80.23]
6 Retained stones (Sensitivity analysis)	7		Odds Ratio (M‐H, Fixed, 95% CI)	Subtotals only
6.1 Good‐outcome analysis	7	617	Odds Ratio (M‐H, Fixed, 95% CI)	0.35 [0.20, 0.60]
6.2 Poor‐outcome analysis	7	617	Odds Ratio (M‐H, Fixed, 95% CI)	0.46 [0.28, 0.76]
6.3 Best‐case for open surgery	7	617	Odds Ratio (M‐H, Fixed, 95% CI)	0.34 [0.20, 0.58]
6.4 Worst‐case for open surgery	7	609	Odds Ratio (M‐H, Fixed, 95% CI)	0.36 [0.21, 0.62]
7 Failure of procedure	7	609	Odds Ratio (M‐H, Fixed, 95% CI)	0.31 [0.19, 0.51]
7.1 Randomisation once CBD stones confirmed	4	275	Odds Ratio (M‐H, Fixed, 95% CI)	0.29 [0.14, 0.60]
7.2 Randomisation on suspicion of bile duct stones	2	236	Odds Ratio (M‐H, Fixed, 95% CI)	0.29 [0.13, 0.66]
7.3 High‐risk participants only	1	98	Odds Ratio (M‐H, Fixed, 95% CI)	0.49 [0.12, 2.08]
8 Hospital stay			Other data	No numeric data
8.1 Randomisation once CBD stones were proven			Other data	No numeric data
8.2 Randomisation on suspicion of CBD stones			Other data	No numeric data
8.3 High‐risk participants only			Other data	No numeric data
9 Cost	1	34	Mean Difference (IV, Fixed, 95% CI)	1102.0 [299.54, 1904.46]