Using computerized assessment in simulated colonoscopy: a validation study

Background and study aims Patient safety during a colonoscopy highly depends on endoscopist competence. Endoscopic societies have been calling for an objective and regular assessment of the endoscopists, but existing assessment tools are time-consuming and prone to bias. We aimed to develop and gather evidence of validity for a computerized assessment tool delivering automatic and unbiased assessment of colonoscopy based on 3 dimensional coordinates from the colonoscope. Methods Twenty-four participants were recruited and divided into two groups based on experience: 12 experienced and 12 novices. Participants performed twice on a physical phantom model with a standardized alpha loop in the sigmoid colon. Data was gathered directly from the Olympus ScopeGuide system providing XYZ-coordinates along the length of the colonoscope. Five different motor skill measures were developed based on the data, named: Travel Length, Tip Progression, Chase Efficiency, Shaft movement without tip progression, and Looping. Results The experinced had a lower travel length (P < 0.001), tip progression (P < 0.001), chase efficiency (P = 0.001) and looping (P = 0.006), and a higher shaft movement without tip progression (P < 0.001) reaching the cecum compared with the novices. A composite score was developed based on the five measurements to create a combined score of progression, the 3D-Colonoscopy-Progression-Score (3D-CoPS). The 3D-CoPS revealed a significant difference between groups (experienced: 0.495 (SD 0.303) and novices –0.454 (SD 0.707), P < 0.001). Conclusion This study presents a novel, real-time computerized assessment tool for colonoscopy, and strong evidence of validity was gathered in a simulation-based setting. The system shows promising opportunities for automatic, unbiased and continuous assessment of colonoscopy performance.

Adenoma and Polyp Detection Rates in Colonoscopy according to Indication

Background. Adenoma detection rate (ADR) is a validated quality measure for screening colonoscopy, but there are little data for other indications. The distribution of adenomas is not well described for these indications. Aim. To describe ADR and the adenoma distribution in the proximal and distal colon based on colonoscopy indication. Methods. Outpatient colonoscopies are subdivided by indication. PDR and ADR for the entire colon and for proximal and distal colon. Data were compared using generalized estimating equations to adjust for clustering amongst endoscopists while controlling for patient age and gender. Results. 3436 colonoscopies were reviewed (51.2%: men (n=1759)). Indications are screening 49.2%, surveillance 29.3%, change in bowel habit 8.4%, bleeding 5.8%, colitides 3.0%, pain 2.8%, and miscellaneous 1.5%. Overall ADR was 37% proximal ADR 28%, and distal ADR 17%. PDR and ADR were significantly higher in surveillance than in screening (PDR: 69% versus 51%; ADR: 50% versus 33%; p=0.0001). Adenomas were more often detected in the proximal than in the distal colon, for all indications. Conclusions. Prevalence of polyps and adenomas differs based on colonoscopy indication. Adenoma detection is highest in surveillance and more commonly detected in the proximal colon. For quality assurance, distinct ADR and PDR targets may need to be established for different colonoscopy indications.