Challenges in planning and initiating a randomized clinical study of sphincter of Oddi dysfunction.

Background: Sphincter of Oddi dysfunction (SOD) is a controversial topic, especially in patients with no objective findings on laboratory or imaging studies (SOD type III). The value of ERCP manometry with sphincterotomy is unproven and carries significant risks.

Objective: To describe the process of planning and initiating a randomized sham-controlled study to establish whether patients with SOD respond to sphincter ablation, and whether the outcomes are predicted by the pain patterns, presence or absence of other functional GI or psychosocial problems, or the results of manometry.