OBJECTIVE: Determine if the increase of the coledocian echographic diameter and partial cholecystectomy are risk factors associated with residual choledocholithiasis in patients treated at the Belen’s Hospital of Trujillo. METHODOLOGY: A retrospective case-control study was carried out. For the cases, 63 clinical records of cholecystectomized patients with residual choledocholithiasis of the HBT were evaluated during the period January 2010 - December 2015. For the controls, the same number of patient histories without residual choledocholithiasis was taken. Frequencies of presentation of the echocardiographic diameter> 10 mm and partial cholecystectomy were calculated for both groups, and were compared using the Z test, considering a level of significance of 0.05. RESULTS: Fifty patients with an echocardiographic diameter> 10mm who developed residual choledocholithiasis were found. In...