How Many Annual Colonoscopies Are Required to Maintain Competence for Surgeons?

David Pace, MD, Mark Borgaonkar, MD, Brad Evans, MD, Curtis Marcoux, Felicia Pickard, Vanessa Falk, Jerry McGrath, Darrell Boone, Chris Smith. Memorial University

Introduction: To determine if the annual case volume of general surgeons (greater or less than 200 colonoscopies) is associated with quality outcomes.

Methods: This retrospective cohort study involved all adults who underwent colonoscopy by a surgeon in the city of St. John’s, NL during the first 6 months of 2012. Subjects were identified through records from the health authority and data was extracted from the electronic medical record (EMR), including the endoscopy procedure report, the nursing record of the endoscopy, and the pathology report. Data was recorded on a standardized data sheet and entered into SPSS version 19.0 for analysis. Univariate analysis was done to determine if there was an association (p<0.10) between quality outcomes (colonoscopy completion rate, adenoma detection rate) and predictors of these outcomes including annual colonoscopy volume, patient age, gender, indication for colonoscopy, and ASA score. Step-wise multivariable logistic regression was then performed to see which variables were independently associated with these quality outcomes. This association is expressed as an odds ratio (OR). A chi-squared test was used to determine if other quality outcomes were associated with annual colonoscopy volume.

Results: Data was collected on 1060 patients. Mean age was 59.5 (sd12.2) years with 550 females. A total of 13 surgeons were studied, of which 6 performed more than 200 annual colonoscopies over the previous 2 years (high volume group) and 7 performed less than 200 annual colonoscopies over the previous 2 years (low volume group). While there was a significant difference in the colonoscopy completion rate between the low volume group and the high volume group (82.2% vs. 91.1%, p<0.001), no difference was noted in the adenoma detection rate between groups (16.7% vs. 17.7%, p=0.762). The regression model revealed that colonoscopy completion was associated with an annual colonoscopy volume of greater than 200 (OR=3.17, p<0.001), an indication of screening or surveillance (OR=1.98, p=0.009), and an ASA score of 1 or 2 (OR=2.29, p=0.020). The adenoma detection rate was associated with older age (OR=1.02, p=0.010) and male gender (OR=2.04, p<0.001). There was no statistically significant association between annual colonoscopy volume and other quality outcome measures including patient discomfort, perioperative hypoxia, use of reversal agents, delayed post-polypectomy bleeding, perforation, and unplanned physician contact within 14 days.

Conclusion: Performing over 200 colonoscopies annually is associated with higher colonoscopy completion rates but does not appear to be associated with other quality measures.