BACKGROUND Laparoscopic cholecystectomy (LC) has become the treatment of choice for patients with symptomatic cholelithiasis. About 8-15 per cent of patients with symptomatic gallstones may bear associated common bile duct (CBD) stones, The management of choledocholithiasis in the laparoscopic era remain debatable. Although pre-operative endoscopic cholangiopancreatography (ERCP) is available and highly accurate in the detection of CBD stones, its routine use is controversial because of its inherent disadvantages. OBJECTIVE The aim of this retrospective study was to generate an effective predictive model for bile duct stones detection by pre-operative ERCP. METHODS Twelve pre-operative clinical, biochemical and sonographic variables from 206 consecutive patients who underwent pre-operative ERCP with LC for gallstones with/without CBD stones from October 1998 to December 2000 were retrospectively analysed RESULTS 143 of the 206 patients with gallstones were found to have CBD stones. The mean age was 61 (20-93) yr old, and 55.9 per cent were female. Multivariate analysis showed a high predictive value for the presence of CBD stones in patients aged > or = 55 yr old (Odd radio (OR) 1.03, 95% confidence interval (95% CI) 1.01-1.05), jaundice (OR 2.7, 95% CI 1.7-4.8), elevated alkaline phosphatase (OR 1.002, 95% CI 1.000-1.005), CBD dilatation on ultrasound (OR 3.8, 95% CI 1.8-8) and CBD stone on ultrasound. CONCLUSIONS The important clinical presentations and investigating could allow more appropriate use of pre-operative ERCP in patients who have symptomatic gallstones with a suspected CBD stone prior to cholecystectomy.