Variation in Colonoscopic Technique and Adenoma Detection Rates at an Academic Gastroenterology Unit

  • Mark E. Benson
  • Mark Reichelderfer
  • Adnan Said
  • Eric A. Gaumnitz
  • Patrick R. Pfau
Original Article


The purpose of this research is to evaluate the quality of colonoscopy at an academic institution with a focus on factors influencing withdrawal times and adenoma detection rates. Procedural data and pathologic results of 550 consecutive screening colonoscopies in average risks patients (mean [±SD] age, 57 ± 7.6, 44% male) completed by ten academic gastroenterologists were reviewed. Per individual gastroenterologist, the adenoma detection rates ranged widely from 0.09 to 0.82 adenomas per patient with a mean of 0.46 for the group. The mean withdrawal time was 7.0 min for the group and ranged from 3.4 to 9.6 min. There was a significant positive relationship between the number of adenomas detected and the withdrawal time (P = 0.006). Endoscopists with cecal intubation time to withdrawal time ratios of less than 1 detected significantly more adenomas compared to endoscopists with ratios greater than 1 (P = 0.001). (1) Significant variation in academic gastroenterologists’ abilities to detect adenomas during screening colonoscopies exists. (2) Colonoscopic withdrawal time and the cecal intubation to withdrawal time ratio are important factors associated with increased adenoma detection rates.


Colonoscopy Adenoma Withdrawal time Intubation time 


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Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  • Mark E. Benson
    • 1
  • Mark Reichelderfer
    • 1
  • Adnan Said
    • 1
  • Eric A. Gaumnitz
    • 1
  • Patrick R. Pfau
    • 1
  1. 1.Section of Gastroenterology and Hepatology, Department of MedicineUniversity of Wisconsin School of Medicine and Public Health, H6/516 Clinical Science CenterMadisonUSA

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