BACKGROUND: There are limited data regarding complications associated with colonoscopy and flexible sigmoidoscopy in usual clinical practice in Canada.OBJECTIVE: To determine the risk factors for lower gastrointestinal (GI) endoscopy-associated complications in usual clinical practice.METHODS: All outpatient lower GI endoscopies performed in Winnipeg (Manitoba) between April 1, 2004 and March 31, 2006, were identified from the provincial physicians’ claims database. All subsequent hospital admissions within 30 days that documented potential complications associated with lower GI endoscopies were identified from the electronic hospital discharges database and reviewed. Multivariate generalized estimating equation regression analysis was performed to determine independent factors (patient, endoscopist and procedure) associated with the risk of developing complications.RESULTS: There were 29,990 outpatient lower GI endoscopies performed in Winnipeg during the years studied. Seventy-seven (0.26%) procedures were associated with complications requiring hospitalization within 30 days of the index procedure. Stricture dilation (rate ratio [RR] 23.14; 95% CI 6.70 to 76.51), polypectomy (RR 5.93; 95% CI 3.66 to 9.62), increasing patient age (for each year increase in age, RR 1.03; 95% CI 1.01 to 1.05) and performance of endoscopy by low-volume endoscopists (fewer than 200 procedures per year, RR 2.28; 95% CI 1.18 to 4.42) and family physicians (RR 2.23; 95% CI 1.39 to 3.58) were independently associated with complications.CONCLUSIONS: The results of the present study suggest that increasing patient age, complex procedures and performance of the index procedure by low-volume endoscopists are independent risk factors for lower GI endoscopy-associated complications in usual clinical practice. This suggests that it may be time to consider implementing minimum volume requirements for endoscopists performing non-screening lower GI endoscopies.