Validation of a novel method for assessing competency in polypectomy

Gastrointest Endosc. 2012 Mar;75(3):568-75. doi: 10.1016/j.gie.2011.09.028. Epub 2011 Dec 9.


Background: There is a gap in the formal assessment of technical skills in polypectomy that is now considered an integral part of colonoscopy. Polypectomy has been shown to reduce the incidence of colorectal cancer but does have associated complications. Polypectomy competency assessment should arguably be a part of the certification process for all endoscopists. A polypectomy competency assessment tool (Direct Observation of Polypectomy Skills [DOPyS]) has been developed and its reliability examined. This study examined the ability of the DOPyS to reliably distinguish between endoscopists with different levels of experience, ie, its construct validity.

Objective: To determine the construct validity of the DOPyS.

Design: Videos of 32 polypectomies (endoscopic view only) were collected from 2 expert (> 1000 colonoscopies) endoscopists (17 polyps) and 6 intermediate-level (100-500 colonoscopies) endoscopists (15 polyps). The videos were edited to include only the entire polypectomy procedure, arranged in random order, and assessed blindly by 4 experienced endoscopists, only 2 of whom were familiar with polypectomy assessment by using the DOPyS before scoring. The differences in overall competency scores (range 1-4; competency, scores ≥ 3) for the expert and intermediate groups were compared by using the Fisher exact test.

Setting: Single center.

Results: The analysis suggested that both trained assessors familiar with the DOPyS could reliably distinguish between the expert and intermediate endoscopists (P = .049 and P < .001), with the expert group scoring higher than the intermediate one. For the assessors with no previous experience of the DOPyS, no such difference could be seen (P = .71 and P = .15).

Limitations: Small sample and polyp size.

Conclusions: The results of the analysis suggested that the DOPyS could reliably differentiate between polypectomies performed by endoscopists of different levels of experience, but only if the assessors were trained in the use of the assessment tool. Training is therefore required to use this tool reliably.

Publication types

  • Validation Study

MeSH terms

  • Clinical Competence*
  • Colonic Polyps / surgery*
  • Colonoscopy / standards*
  • Humans