Original article Clinical endoscopy| Volume 90, ISSUE 4, P651-655.e3, October 2019

Improvement in colonoscopy quality metrics in clinical practice from 2000 to 2014

      Background and Aims

      There has been a tremendous increase in research focused on quality metrics in colonoscopy since 2000. However, whether national performance in colonoscopy quality outcomes has changed significantly since then is not as well known.


      We examined colonoscopy data collected prospectively through the Clinical Outcomes Research Initiative, which included 84 GI practice sites from 2000 to 2014 for patients undergoing colonoscopy for multiple indications. Colonoscopy outcomes by indication were compared across three 5-year periods (2000-2004, 2005-2009, 2010-2014) using the following metrics: bowel preparation quality (percentage good/excellent), finding a polyp, finding 2 or more polyps, and finding a polyp >9 mm. Multivariate logistic regression was used to generate odds ratios and 95% confidence intervals for each time period while controlling for age, gender, and race/ethnicity.


      A total of 1,541,837 adults were included in the study across all indication groups. The average-risk screening group (390,741 adults) demonstrated statistically significant improvement across all 4 quality metrics when comparing the baseline period with the final time period. Bowel preparation quality improved across all indications when comparing the baseline period with the final time period. Finding a polyp, finding 2 or more polyps, and finding a polyp >9 mm improved in the average-risk screening, surveillance, and diagnostic indication groups when comparing the baseline period with the final time period. The increased-risk screening and inflammatory bowel disease indication groups did not see improvements beyond bowel preparation quality when comparing the baseline with the final time period.


      Colonoscopy outcomes as measured by bowel preparation quality, finding a polyp, finding 2 or more polyps, and finding a polyp >9 mm improved significantly over the 15-year period between 2000 and 2014, with the largest and most consistent impact in the average-risk screening indication group.


      ACG (American College of Gastroenterology), ADR (adenoma detection rate), AGA (American Gastroenterologic Association), ASA (American Society of Anesthesiologists), ASGE (American Society for Gastrointestinal Endoscopy)
      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to Gastrointestinal Endoscopy
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


        • Kohn L.T.
        • Corrigan J.M.
        • Donaldson M.S.
        • Institute of Medicine
        To err is human: building a safer health system.
        National Academy Press, Washington, DC2000
        • Rex D.K.
        • Bond J.H.
        • Winawer S.
        • et al.
        Quality in the technical performance of colonoscopy and the continuous quality improvement process for colonoscopy: recommendations of the U.S. Multi-Society Task Force on Colorectal Cancer.
        Am J Gastroenterol. 2002; 97: 1296-1308
        • Brotman M.
        • Allen J.I.
        • Bickston S.J.
        • et al.
        AGA Task Force on Quality in Practice: a national overview and implications for GI practice.
        Gastroenterology. 2005; 129: 361-369
        • Rex D.K.
        • Petrini J.L.
        • Baron T.H.
        • et al.
        Quality indicators for colonoscopy.
        Am J Gastroenterol. 2006; 101: 873-885
        • Lieberman D.
        • Nadel M.
        • Smith R.
        • et al.
        Standardized colonoscopy reporting and data system (CO-RADS): report of the Quality Assurance Task Group of the National Colorectal Cancer Roundtable.
        Gastrointest Endosc. 2007; 65: 757-766
        • Rex D.K.
        • Schoenfeld P.S.
        • Cohen J.
        • et al.
        Quality indicators for colonoscopy.
        Gastrointest Endosc. 2015; 81: 31-53
        • Centers for Medicare and Medicaid Services
        Measure codes.
        (Available at:)
        • Kaminski M.F.
        • Regula J.
        • Kraszewska E.
        • et al.
        Quality indicators for colonoscopy and the risk of interval cancer.
        N Engl J Med. 2010; 362: 1795-1803
        • Corley D.
        • Jensen C.D.
        • Marks A.R.
        • et al.
        Adenoma detection rate and risk of colorectal cancer and death.
        N Engl J Med. 2014; 370: 1298-1306
        • Schramm C.
        • Scheller I.
        • Franklin J.
        • et al.
        Predicting ADR from PDR and individual adenoma-to-polyp-detection-rate ratio for screening and surveillance colonoscopies: a new approach to quality assessment.
        United European Gastroenterol J. 2017; 5: 742-749
        • Baxter N.
        • Sutradhar R.
        • Forbes D.D.
        • et al.
        Analysis of administrative data finds endoscopist quality measures associated with post-colonoscopy colorectal cancer.
        Gastroenterology. 2011; 140: 65-72
        • Lieberman D.A.
        • Rex D.K.
        • Winawer S.J.
        • et al.
        Guidelines for colonoscopy surveillance after screening and polypectomy: a consensus update by the US Multi-Society Task Force on Colorectal Cancer.
        Gastroenterology. 2012; 143: 844-857