A proof-of-principle, prospective, randomized, controlled trial demonstrating improved outcomes in scheduled unsedated colonoscopy by the water method.

Background: An observational study in veterans showed that a novel water method (water infusion in lieu of air insufflation) enhanced cecal intubation and willingness to undergo a repeat scheduled unsedated colonoscopy.

Objective: To confirm these beneficial effects and significant attenuation of discomfort in a randomized, controlled trial (RCT).

Design: Prospective RCT, intent-to-treat analysis.