Patients with pancreaticobiliary pain or idiopathic pancreatitis have been classified as having definitive (type I), presumptive (type II), or possible (type III) sphincter of Oddi dysfunction (SOD) based on clinical, laboratory, and ERCP data. This study was undertaken to determine the frequency of abnormal sphincter of Oddi manometry (SOM) when patients are classified by this system. Two hundred and thirteen patients with pancreaticobiliary pain were evaluated clinically; SOM, ERCP, and ductal contrast drainage time tests were performed. For biliary types I, II, and III, the frequency of abnormal SOM was 85.7%, 55.1%, and 28.1%, respectively. Similarly, for pancreatic types I, II, and III, an elevated basal sphincter pressure occurred in 92.3%, 58.2%, and 35.1%, respectively. When patients with an abnormal basal sphincter pressure were characterized by the magnitude of the elevation, the manometric profiles were similar for types I, II, and III. These data suggest that elevated sphincter pressure occurs more frequently in type III patients than previously reported, and supports consideration of SOM when evaluating and treating type II and type III patients.