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Factors determining the quality of screening colonoscopy: a prospective study on adenoma detection rates, from 12 134 examinations (Berlin colonoscopy project 3, BECOP-3)
  1. Andreas Adler1,
  2. Karl Wegscheider2,
  3. David Lieberman3,
  4. Alireza Aminalai4,
  5. Jens Aschenbeck4,
  6. Rolf Drossel4,*,
  7. Michael Mayr4,
  8. Michael Mroß4,
  9. Mathias Scheel4,
  10. Andreas Schröder4,
  11. Katharina Gerber5,
  12. Gabriela Stange1,
  13. Stephanie Roll6,
  14. Ulrich Gauger7,
  15. Bertram Wiedenmann8,
  16. Lutz Altenhofen9,
  17. Thomas Rosch10
  1. 1Central Interdisciplinary Endoscopy, Charité Medical University, Campus Virchow Hospital, Berlin, Germany
  2. 2Department of Medical Biometry and Epidemiology, University Hospital Hamburg-Eppendorf, Hamburg, Germany
  3. 3Division of Gastroenterology, Portland VA Medical Centre, Portland, Oregon, USA
  4. 4Private Practice in Gastroenterology, Berlin, Germany
  5. 5Department of Interdisciplinary Endoscopy, University Hospital Hamburg-Eppendorf, Berlin Study Group Office, Berlin, Germany
  6. 6Charité Medical University, Campus Mitte Hospital, Institute for Social Medicine, Epidemiology and Health economy, Berlin, Germany
  7. 7Berlin Statistical Office, Berlin, Germany
  8. 8Charite, Universitatsmedizin Berlin, Campus virchow-klinikum, MED KLINIK M.S. Hepatologie U. Gastroenterologie, Berlin, Germany
  9. 9Central Research Institute of Ambulatory Health Care, Berlin, Germany
  10. 10Department of Interdisciplinary Endoscopy, University Hospital Hamburg-Eppendorf, Hamburg, Germany
  1. Correspondence to Professor Thomas Rosch, Department of Interdisciplinary Endoscopy, University Hospital Hamburg-Eppendorf, Martinistr. 52, Hamburg 20246, Germany; t.roesch{at}


Background Screening colonoscopy (SC) outcome quality is best determined by the adenoma detection rate (ADR). The substantial variability in the ADRs between endoscopists may reflect different skills, experience and/or equipment.

Objective To analyse the potential factors that may influence ADR variance, including case volume.

Design 12 134 consecutive SCs (mean age 64.5 years, 47% men) from 21 Berlin private-practice colonoscopists were prospectively studied during 18 months. The data were analysed using a two-level mixed linear model to adequately address the characteristics of patients and colonoscopists. The ADR was regressed after considering the following factors: sex, age, bowel cleanliness, NSAID intake, annual SC case volume, lifetime experience, instrument withdrawal times, instrument generations used, and the number of annual continuing medical education (CME) meetings attended by the physician. The case volume was also retrospectively analysed from the 2007 national SC registry data (312 903 colonoscopies and 1004 colonoscopists).

Results The patient factors that correlated with the ADR were sex, age (p<0.001) and low quality of bowel preparation (p=0.005). The factors that were related to the colonoscopists were the number of CME meetings attended (p=0.012) and instrument generation (p=0.001); these factors accounted for approximately 40% of the interphysician variability. Within a narrow range (6–11 min), the withdrawal time was not correlated with the ADR. Annual screening case volume did not correlate with the ADR, and this finding was confirmed by the German registry data.

Conclusions The outcome quality of screening colonoscopies is mainly influenced by individual colonoscopist factors (ie, CME activities) and instrument quality.

Clinical trial registration number Clinical Trial Gov Registration number: NCT00860665.

  • Screening colonoscopy
  • quality assurance
  • quality factors
  • adenoma detection rate
  • barretts oesophagus
  • endoscopy
  • neuropeptides
  • adhesion molecules
  • neuroendocrine cells
  • somatostatin
  • neuroendocrine tumours
  • colonoscopy
  • colonic polyps
  • endoscopic retrograde pancreatography
  • endoscopic sphincterotomy
  • endoscopic ultrasonography

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  • * RD Deceased October 2011.

  • Funding The Berlin Colonoscopy Screening Study was supported by a grant from Deutsche Krebshilfe e.V. (no. 108166) and by unrestricted grants from Olympus, Pentax and Falk Companies. There was no influence on study design, performance, data analysis or the writing of the manuscript.

  • Competing interests None.

  • Ethics approval Charité Ethical Committee (nr. EA 02/019/07).

  • Provenance and peer review Not commissioned; externally peer reviewed.