BACKGROUND: Wait times for hospital screening colonoscopy have increased dramatically in recent years, resulting in an increase in patient referrals to office-based endoscopy clinics. There is no formal regulation of office endoscopy, and it has been suggested that the quality of service in some office locations may be inferior to hospital procedures.OBJECTIVE: To compare the quality of office-based screening colonos-copies at a clinic in Oakville, Ontario, with published benchmarks for cecal intubation, withdrawal times, polyp detection, adenoma detection, cancer detection and patient complications.METHODS: Demographic information on consecutive patients and colonoscopy reports by all nine gastroenterologists at the Oakville Endoscopy Centre between August 2006 and December 2007 were prospectively obtained.RESULTS: A total of 3741 colonoscopies were analyzed. The mean age of patients was 57.1 years and 51.9% were women. The cecal intubation rate was 98.98% with an average withdrawal time of 9.75 min. A total of 3857 polyps were retrieved from 1725 patients (46.11%), and 1721 adenomas were detected in 953 patients (25.47%). A total of 126 patients (3.37%) had advanced polyps and 18 (0.48%) were diagnosed with colon cancer. One patient (0.027%) had a colonic perforation and two patients had postpolypectomy bleeding (0.053%). These results meet or exceed published benchmarks for quality colonoscopy.CONCLUSIONS: The Oakville Endoscopy Centre data demonstrate that office-based colonoscopies, performed by well-trained physicians using adequate sedation and hospital-grade equipment, result in outcomes at least equal to or better than those of published academic/community hospital practices and are therefore a viable option for the future of screening colonoscopy in Canada.