Variability in, and factors associated with, sizing of polyps by endoscopists at a large community practice

Accurate sizing of polyps at time of colonoscopy is critical for determining surveillance intervals. Endoscopists routinely over- or underestimate the size of polyps at colonoscopy. We evaluated the variability in sizing of polyps among multiple endoscopists, and the effect of patient and physician related factors on polyp size estimation in a large community-based practice.

Adult patients who underwent a colonoscopy with polypectomy at five endoscopy centers in Minneapolis/St. Paul by one of 52 endoscopists in 2013 were included in this study. Association of patient, physician, and procedure related factors on polyp sizing was assessed.

In the study time frame, 38 624 colonoscopies were performed at five ambulatory endoscopy centers. Of these, 16 336 had one or more polyp removed with size information available, and were included in this analysis. There was significant inter-physician variation for estimating polyp sizes larger than 5 mm (intraclass correlation coefficient [ICC] 0.13). Older patient age (OR 1.08, 95 %CI 1.06 - 1.11), and male physician gender (OR 1.92, 95 %CI 1.26 - 2.94) were associated with increased odds of physicians sizing polyps as larger in size. Surveillance procedures had a higher odds of larger polyp sizing compared to screening (OR 0.91, 95 %CI 0.86 - 0.97) and diagnostic procedures (OR 0.86, 95 %CI 0.78 - 0.94).

In a large community setting, variation of polyp sizing estimates exists between physicians. Male physicians were more likely to size polyps as larger in size. Older patients and patients undergoing surveillance procedures were more likely to have polyps that were sized as larger in size.