Laparoscopic ultrasonography versus intra-operative cholangiogram for the detection of common bile duct stones during laparoscopic cholecystectomy: A meta-analysis of diagnostic accuracy - Aziz,O; Ashrafian,H; Jones,C; Harling,L; Kumar,S; Garas,G; Holme,T; Darzi,A; Zacharakis,E; Athanasiou,T (INTERNATIONAL JOURNAL OF SURGERY, 2014)