Selection criteria for preoperative endoscopic retrograde cholangiopancreatography before laparoscopic cholecystectomy and endoscopic treatment of bile duct stones: Results of a retrospective, single center study between 1996-2002

Table 7 Association between the number of positive predic-tive factors and ERCP findings (n = 206)

Number of positive factors	Number	Stone	Negative	Unsuccessful	%
1	84	1	80	3	1.2
2	46	19	25	2	43.1
3	40	29	11	0	72.5
≥ 4	36	32	3	1	91.4

P < 0.00001 for the whole group, P < 0.00001, between group 1 and groups 2, 3, 4, group 2 and group 4, P = 0.008, between groups 2 and 3, P = 0.035, between groups 3 and 4.