Background: An endoscopists adenoma detection rate (ADR) of less than 20 % correlates with high risk for occurrence of interval cancer. The impact of high-definition (HD) imaging on the ADR is discussed controversially. We aimed to investigate whether detection rates of individual endoscopists increase within 1 year before and 1 year after the switch from standard to HD endoscopy.
Methods: This cohort study analyzed 6,330 screening colonoscopies (2,968 with standard and 3,362 with HD) performed by 42 endoscopists between November 2007 and March 2013 within a nationwide quality assurance program for screening colonoscopy.
Results: The ADR of endoscopists with a low ADR (<20 %) increased significantly higher (from 11.8 to 18.1 %, p = 0.003) than of those with a high ADR (≥ 20 %) (from 28.6 to 30.7 %, p = 0.439) after switch from standard to HD colonoscopes (p = 0.0076). The proportion of endoscopists with an ADR < 20 % decreased from 45 to 42.9 % (p = 0.593). There was no significant increase in age- and sex-adjusted detection rates of adenomas (20.2 vs 23.7 %; p = 0.089), advanced adenomas (4.7 vs 5.5 %; p = 0.479), flat adenomas (2.7 vs 3.1 %; p = 0.515), polyps (38.8 vs 41.5 %; p = 0.305), proximal polyps (18.5 vs 20 %; p = 0.469) and hyperplastic polyps (15 vs 17.2 %; p = 0.243) of endoscopists after switch to HD colonoscopes. There was no difference in detection rates of flat polyps (5.5 vs 5.5 %; p = 0.987).
Conclusions: The use of HD scopes is associated with marginal improvement in adenoma detection rates limited to those endoscopists with low adenoma detection rates prior to its introduction.