Fellow involvement may increase adenoma detection rates during colonoscopy

Adenoma detection rate (ADR) is increasingly used as a quality indicator for screening/surveillance colonoscopy. Recent investigations to identify factors that affect ADR have focused on the technical aspects of the procedure or the equipment.

To assess whether gastroenterology (GI) fellow participation during colonoscopy affects ADR.

This is a retrospective study of data prospectively collected on 309 patients enrolled in a different study not involving polyp detection. In total, 126 colonoscopies were performed by a GI attending alone, and 183 by a GI fellow supervised by one of the same four GI attendings.

The ADR was significantly higher when a fellow was involved (37% vs 23%, P < 0.01), as was the total number of adenomas detected (0.56 per patient vs 0.30 per patient, P < 0.05). The percentage of patients with two and three or more adenomas was also higher for fellows versus attendings alone (13.1% vs 5.6%, and 6% vs 1.6%, respectively; P < 0.05), though there was no difference in the detection of advanced adenomas (7.1% vs 5.6%, P = 0.16). The adenomas detected when fellows participated were smaller (mean size 4.4 mm vs 5.8 mm, P < 0.05), and more likely to be sessile (80.6% vs 64.9%, P < 0.05). There were no significant differences in the age, gender, indication for colonoscopy, or procedure time for the two groups.

In this retrospective study, fellow involvement in colonoscopy may increase not only the ADR, but also the detection of more subtle adenomas. Further investigation into whether this is a "fellow effect," or simply a matter of more efficient visual scanning and recognition with two people, should be considered.