Learning Curves for Colonoscopy: a Prospective Evaluation of Gastroenterology Fellows at a Single Center

Background/aims: Colonoscopy training programs and the minimal experience with colonoscopy required to be considered technically competent are not well established. The aim of this study was to determine the colonoscopy learning curves and factors associated with this difficult procedure at a single center.

Methods: A total of 3,243 colonoscopies were performed by 12 first-year gastroenterology fellows, and various clinical factors were assessed prospectively for 22 months. Acquisition of competence (success rate) was evaluated based on two objective criteria: (i) the adjusted completion rate (>90%) and (ii) cecal intubation time (<20 minutes).

Results: The overall success rate in reaching the cecum in less than 20 minutes was 72.8%. The cecal intubation time was 9.34+/-4.13 minutes (mean+/-SD). Trainees' skill at performing cecal intubation in <20 minutes reached the requisite standard of competence after 200 procedures. Cecal intubation time decreased significantly from 11.3 to 9.4 minutes after 100 procedures and improved continuously thereafter. Female patients and advanced patient age (over 60 years) were associated with prolonged cecal intubation time (>20 minutes). Surgery of the uterus and ovaries was significantly correlated with delayed cecal intubation time, but not after sufficient colonoscopy experience.

Conclusions: The minimum number of procedures to reach technical competence was 200. The cecal intubation time was longer in female and older patients.