Quantification of Adequate Bowel Preparation for Screening or Surveillance Colonoscopy in Men

Published:October 03, 2015DOI:https://doi.org/10.1053/j.gastro.2015.09.041

      Background & Aims

      Bowel preparation is defined as adequate if it is sufficient for identification of polyps greater than 5 mm. However, adequate preparation has not been quantified. We performed a prospective observational study to provide an objective definition of adequate preparation, based on the Boston Bowel Prep Scale (BBPS, which consists of 0–3 points for each of 3 colon segments).


      We collected data from 438 men who underwent screening or surveillance colonoscopies and then repeat colonoscopy examinations within 60 days by a different blinded endoscopist (1161 colon segments total) at the West Haven Veterans Affairs Medical Center from January 2014 to February 2015. Missed polyps were defined as those detected on the second examination of patients with the best possible bowel preparation (colon segment BBPS score of 3) on the second examination. The primary outcome was the proportion of colon segments with adenomas larger than 5 mm that were missed in the first examination. We postulated that the miss rate was noninferior for segments with BBPS scores of 2 vs those with BBPS scores of 3 (noninferiority margin, <5%). Our secondary hypotheses were that miss rates were higher in segments with BBPS scores of 1 vs those with scores of 3 or of 2.


      The adjusted proportion with missed adenomas greater than 5 mm was noninferior for segments with BBPS scores of 2 (5.2%) vs those with BBPS scores of 3 (5.6%) (a difference of -0.4%; 95% confidence interval [CI], -2.9% to 2.2%). Of study subjects, 347 (79.2%) had BBPS scores of 2 or greater in all segments on the initial examination. A higher proportion of segments with BBPS scores of 1 had missed adenomas larger than 5 mm (15.9%) than segments with BBPS scores of 3 (5.6%) (a difference of 10.3%; 95% CI, 2.7%–17.9%) or 2 (5.2%) (a difference of 10.7%; 95% CI, 3.2%–18.1%). Screening and surveillance intervals based solely on the findings at the first examination would have been incorrect for 16.3% of patients with BBPS scores of 3 in all segments, for 15.3% with BBPS scores of 2 or 3 in all segments, and for 43.5% of patients with a BBPS score of 1 in 1 or more segments.


      Patients with BBPS scores of 2 or 3 for all colon segments have adequate bowel preparation for the detection of adenomas larger than 5 mm and should return for screening or surveillance colonoscopy at standard guideline-recommended intervals. Colon segments with a BBPS score of 1 have a significantly higher rate of missed adenomas larger than 5 mm than segments with scores of 2 or 3. This finding supports a recommendation for early repeat colonoscopic evaluation in patients with a BBPS score of 0 or 1 in any colon segment.


      Abbreviations used in this paper:

      ADR (adenoma detection rate), BBPS (Boston Bowel Preparation Scale), CI (confidence interval)
      To read this article in full you will need to make a payment
      AGA Member Login
      Login with your AGA username and password.
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect


        • Zauber A.G.
        • Winawer S.J.
        • O'Brien M.J.
        • et al.
        Colonoscopic polypectomy and long-term prevention of colorectal-cancer deaths.
        N Engl J Med. 2012; 366: 687-696
        • Nishihara R.
        • Wu K.
        • Lochhead P.
        • Morikawa T.
        • et al.
        Long-term colorectal-cancer incidence and mortality after lower endoscopy.
        N Engl J Med. 2013; 369: 1095-1105
        • Citarda F.
        • Tomaselli G.
        • Capocaccia R.
        • et al.
        Efficacy in standard clinical practice of colonoscopic polypectomy in reducing colorectal cancer incidence.
        Gut. 2001; 48: 812-815
        • Rex D.K.
        • Johnson D.A.
        • Anderson J.C.
        • et al.
        American College of Gastroenterology guidelines for colorectal cancer screening 2009 [corrected].
        Am J Gastroenterol. 2009; 104: 739-750
        • Peery A.F.
        • Dellon E.S.
        • Lund J.
        • et al.
        Burden of gastrointestinal disease in the United States: 2012 update.
        Gastroenterology. 2012; 143: 1179-1187.e1-3
        • Rex D.K.
        • Schoenfeld P.S.
        • Cohen J.
        • et al.
        Quality indicators for colonoscopy.
        Gastrointest Endosc. 2015; 81: 31-53
        • Johnson D.A.
        • Barkun A.N.
        • Cohen L.B.
        • et al.
        Optimizing adequacy of bowel cleansing for colonoscopy: recommendations from the US multi-society task force on colorectal cancer.
        Gastroenterology. 2014; 147: 903-924
        • 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
        • Ben-Horin S.
        • Bar-Meir S.
        • Avidan B.
        The impact of colon cleanliness assessment on endoscopists' recommendations for follow-up colonoscopy.
        Am J Gastroenterol. 2007; 102: 2680-2685
        • Calderwood A.H.
        • Jacobson B.C.
        Comprehensive validation of the Boston Bowel Preparation Scale.
        Gastrointest Endosc. 2010; 72: 686-692
        • Menees S.B.
        • Elliott E.
        • Govani S.
        • et al.
        The impact of bowel cleansing on follow-up recommendations in average-risk patients with a normal colonoscopy.
        Am J Gastroenterol. 2014; 109: 148-154
        • Saini S.D.
        • Nayak R.S.
        • Kuhn L.
        • et al.
        Why don't gastroenterologists follow colon polyp surveillance guidelines?: results of a national survey.
        J Clin Gastroenterol. 2009; 43: 554-558
        • Hillyer G.C.
        • Basch C.H.
        • Lebwohl B.
        • et al.
        Shortened surveillance intervals following suboptimal bowel preparation for colonoscopy: results of a national survey.
        Int J Colorectal Dis. 2013; 28: 73-81
        • Laiyemo A.O.
        • Pinsky P.F.
        • Marcus P.M.
        • et al.
        Utilization and yield of surveillance colonoscopy in the continued follow-up study of the polyp prevention trial.
        Clin Gastroenterol Hepatol. 2009; 7 (quiz 497): 562-567
        • Schoen R.E.
        • Pinsky P.F.
        • Weissfeld J.L.
        • et al.
        Utilization of surveillance colonoscopy in community practice.
        Gastroenterology. 2010; 138: 73-81
        • Ransohoff D.F.
        • Yankaskas B.
        • Gizlice Z.
        • et al.
        Recommendations for post-polypectomy surveillance in community practice.
        Dig Dis Sci. 2011; 56: 2623-2630
        • Lai E.J.
        • Calderwood A.H.
        • Doros G.
        • et al.
        The Boston bowel preparation scale: a valid and reliable instrument for colonoscopy-oriented research.
        Gastrointest Endosc. 2009; 69: 620-625
        • Enestvedt B.K.
        • Eisen G.M.
        • Holub J.
        • et al.
        Is the American Society of Anesthesiologists classification useful in risk stratification for endoscopic procedures?.
        Gastrointest Endosc. 2013; 77: 464-471
        • Rex D.K.
        • Cutler C.S.
        • Lemmel G.T.
        • et al.
        Colonoscopic miss rates of adenomas determined by back-to-back colonoscopies.
        Gastroenterology. 1997; 112: 24-28
        • Calderwood A.H.
        • Schroy 3rd, P.C.
        • Lieberman D.A.
        • et al.
        Boston Bowel Preparation Scale scores provide a standardized definition of adequate for describing bowel cleanliness.
        Gastrointest Endosc. 2014; 80: 269-276
        • Aronchick C.A.
        • Lipshutz W.H.
        • Wright S.H.
        • et al.
        A novel tableted purgative for colonoscopic preparation: efficacy and safety comparisons with Colyte and Fleet Phospho-Soda.
        Gastrointest Endosc. 2000; 52: 346-352
        • Rostom A.
        • Jolicoeur E.
        Validation of a new scale for the assessment of bowel preparation quality.
        Gastrointest Endosc. 2004; 59: 482-486
        • van Rijn J.C.
        • Reitsma J.B.
        • Stoker J.
        • et al.
        Polyp miss rate determined by tandem colonoscopy: a systematic review.
        Am J Gastroenterol. 2006; 101: 343-350
        • Hong S.N.
        • Sung I.K.
        • Kim J.H.
        • et al.
        The effect of the bowel preparation status on the risk of missing polyp and adenoma during screening colonoscopy: a tandem colonoscopic study.
        Clin Endosc. 2012; 45: 404-411
        • Adler A.
        • Wegscheider K.
        • Lieberman D.
        • et al.
        Factors determining the quality of screening colonoscopy: a prospective study on adenoma detection rates, from 12,134 examinations (Berlin colonoscopy project 3, BECOP-3).
        Gut. 2013; 62: 236-241
        • Froehlich F.
        • Wietlisbach V.
        • Gonvers J.J.
        • et al.
        Impact of colonic cleansing on quality and diagnostic yield of colonoscopy: the European Panel of Appropriateness of Gastrointestinal Endoscopy European multicenter study.
        Gastrointest Endosc. 2005; 61: 378-384
        • Harewood G.C.
        • Sharma V.K.
        • de Garmo P.
        Impact of colonoscopy preparation quality on detection of suspected colonic neoplasia.
        Gastrointest Endosc. 2003; 58: 76-79
        • Sherer E.A.
        • Imler T.D.
        • Imperiale T.F.
        The effect of colonoscopy preparation quality on adenoma detection rates.
        Gastrointest Endosc. 2012; 75: 545-553
        • Radaelli F.
        • Meucci G.
        • Sgroi G.
        • et al.
        Technical performance of colonoscopy: the key role of sedation/analgesia and other quality indicators.
        Am J Gastroenterol. 2008; 103: 1122-1130
        • de Jonge V.
        • Sint Nicolaas J.
        • Cahen D.L.
        • et al.
        Quality evaluation of colonoscopy reporting and colonoscopy performance in daily clinical practice.
        Gastrointest Endosc. 2012; 75: 98-106
        • Clark B.T.
        • Rustagi T.
        • Laine L.
        What level of bowel prep quality requires early repeat colonoscopy: systematic review and meta-analysis of the impact of preparation quality on adenoma detection rate.
        Am J Gastroenterol. 2014; 109 (quiz 1724): 1714-1723

      Linked Article