Individual polyp detection rate in routine daily endoscopy practice depends on case-mix

The adenoma detection rate (ADR), a marker of endoscopic quality, is confounded by selection bias. It is not known what the ADR is in normal daily practice.

To study the polyp detection rate (PDR) in different endoscopists in the course of years.

All consecutive endoscopies of the colon done in 11 years were included. Endoscopies in the regular surveillance programme after polyp removal and after surgery because of colorectal cancer or diverticular disease were scored separately. The number of yearly procedures per endoscopist and presence of polyps, anastomoses, surveillance and cancer were noted.

In the period of 11 years, 14,908 consecutive endoscopies of colon and rectum were done by four endoscopists. Two endoscopists had a significantly lower PDR than the other two (p < 0.001), these two had the longest careers in endoscopy. The two younger endoscopists did significantly less often procedures in patients with anastomoses and because of surveillance (p < 0.001, respectively). One endoscopist detected significantly less colorectal cancers than the other three endoscopists (p < 0.001).

This study presents the PDR in normal routine daily endoscopy practice. It can be concluded that the PDR, implicating the ADR, in unselected patients can be lower in individual endoscopists than recommended in the literature. This highly depends on the case-mix of patients presented for endoscopy. This result debates the use of the ADR as quality indicator for individual endoscopists.