The presence of a periampullary duodenal diverticulum (PDD) is often observed during upper digestive tract barium meal studies and endoscopic retrograde cholangiopancreatography (ERCP). The impact of periampullary duodenal diverticulum for the formation of gallstones in the bile duct (choledocholithiasis) is widely accepted. In this study it using logistic regression modeling the appearance of choledocholithiasis depending periampullary duodenal diverticulum, to confirm the connection between them. The resulting model allows evaluation of the estimated probability of occurrence of this complication. The model is based on the 1719 recording of endoscopic retrograde cholangiopancreatography performed in the