An explorative study from the Norwegian Quality Register Gastronet comparing self-estimated versus registered quality in colonoscopy performance

Background and study aims: The value of a colonoscopy quality assurance (QA) register may be questioned if it brings no new information on which to act for quality improvement, e. g. if self-assessed quality of colonoscopy performance correlates perfectly with registered performance. Patients and methods: In this explorative study, 39 (33 Norwegian and 6 Swedish) out of 99 new endoscopists joining the Norwegian QA register Gastronet from 2008 to 2013 responded to an invitation to fill in a questionnaire for self-assessment of cecal intubation rate, polyp detection rate for polyps ≥ 5 mm (PDR-5 mm), withdrawal time, total examination time, and rates for severely painful and pain-free colonoscopies before receiving their first-time feedback of actually registered results from Gastronet. A linear regression analysis was applied to explore the correlation between experience level and quality of estimation. Results: We included 2654 colonoscopies in our study. Endoscopists underestimated their cecal intubation rate (estimated 88.8 %, registered 93.1 %, P < 0.001), total procedure time (estimated 31.7 minutes, registered 37.2 minutes, P = 0.014), withdrawal time (estimated 9.8 minutes, registered 14.4 minutes, P = 0.006) and the rate of pain-free procedures (estimated 18.3 %, registered 24.5 %, P = 0.001). Pre-study colonoscopy experience was not correlated with estimated quality for any of the indicators. Conclusions: Apart from overestimation of severely painful examinations, endoscopists most often underestimated their colonoscopy performance. Self-assessed quality of colonoscopy performance may not be a satisfactory substitute for systematic registration of quality and not sufficiently valid to be acted upon.