This is the protocol for a review and there is no abstract. The objectives are as follows:
To determine and compare the accuracy of different tests for the diagnosis of common bile duct stones in each of the three steps of the diagnostic pathway, as described in Figure 1, in terms of sensitivity and specificity. We plan to compare the two tests from each step of the diagnostic pathway in a separate review, that is, liver function tests versus abdominal ultrasound, endoscopic ultrasound versus MRCP, and ERCP versus intraoperative cholangiography. This is a generic protocol for these three reviews.
The secondary objective of this review is to investigate the variation of the test accuracy according to the various sources of heterogeneity mentioned in the section 'Investigation of sources of heterogeneity'.