Comparison 1.

Guidewire‐assisted cannulation versus contrast‐assisted cannulation, main analysis

Outcome or subgroup title	No. of studies	No. of participants	Statistical method	Effect size
1 Post‐ERCP pancreatitis (ITT)	12	3450	Risk Ratio (M‐H, Random, 95% CI)	0.51 [0.32, 0.82]
2 Post‐ERCP pancreatitis (per‐protocol)	12	3331	Risk Ratio (M‐H, Random, 95% CI)	0.51 [0.32, 0.83]
3 Severity of post‐ERCP pancreatitis	10		Risk Ratio (M‐H, Random, 95% CI)	Subtotals only
3.1 Mild post‐ERCP pancreatitis	10	2986	Risk Ratio (M‐H, Random, 95% CI)	0.49 [0.26, 0.93]
3.2 Moderate post‐ERCP pancreatitis	10	2986	Risk Ratio (M‐H, Random, 95% CI)	0.76 [0.34, 1.67]
3.3 Severe post‐ERCP pancreatitis	10	2986	Risk Ratio (M‐H, Random, 95% CI)	0.84 [0.28, 2.48]
4 Need for 'crossover' to the alternative technique (in 'crossover' studies)	4	1256	Risk Ratio (M‐H, Random, 95% CI)	0.65 [0.38, 1.13]
5 Secondary cannulation success (after technique 'crossover' in 'crossover' studies)	4	269	Risk Ratio (M‐H, Random, 95% CI)	0.74 [0.41, 1.31]
6 Overall cannulation success	12	3450	Risk Ratio (M‐H, Random, 95% CI)	1.01 [0.99, 1.04]
7 The need for precut sphincterotomy	8	2386	Risk Ratio (M‐H, Random, 95% CI)	0.75 [0.60, 0.95]
8 Inadvertent pancreatic duct injection or cannulation	8	2524	Risk Ratio (M‐H, Random, 95% CI)	0.88 [0.76, 1.01]
9 Post‐sphincterotomy bleeding	5	1480	Risk Ratio (M‐H, Random, 95% CI)	0.93 [0.50, 1.72]
10 Perforation	6	1880	Risk Ratio (M‐H, Random, 95% CI)	1.53 [0.06, 41.19]
11 Primary cannulation success (with the randomised technique before technique 'crossover' or precut)	10	2986	Risk Ratio (M‐H, Random, 95% CI)	1.07 [1.00, 1.15]