Quality indicators for colonoscopy: Current insights and caveats

Table 1 Quality indicators and their shortcomings

Quality indicator	Proposed standard	Unresolved issues
Bowel preparation	Each endoscopy report should state the quality of the bowel preparation[18,19] ≥ 90% of patients undergoing colonoscopy should have had a bowel preparation rated as excellent or at least adequate[19,20]	No evidence to support a cut-off of ≥ 90% No clear and generally accepted definition of adequate bowel preparation Unclear what bowel preparation quality is the absolute minimum to detect relevant findings and prevent interval cancers No clear policy on how to proceed in case of inadequate bowel preparation
Cecal intubation rate	Overall cecal intubation rate of ≥ 90%[18-20] Adjusted cecal intubation rate of ≥ 95%[18,19] Cecal intubation rate of ≥ 95% in all screening colonoscopies[18,19]	No robust scientific evidence to support a cut-off of ≥ 90% No evidence supporting an association between cecal intubation rate and the occurrence of interval CRC
Withdrawal time	≥ 6 min on withdrawal from cecal pole to anus[18-20]	Conflicting reports on the association between withdrawal time and the number of detected polyps Interventions directed at optimizing withdrawal time have yielded conflicting results No evidence supporting an association between withdrawal time and the occurrence of interval CRC Better endoscopic withdrawal technique is not necessarily associated with withdrawal time An indirect measure to quantify the proportion of the colonic mucosa that is adequately visualized
Adenoma detection rate	≥ 25% in men and ≥ 15% in women over 50 yr[18] ≥ 35% of all screening colonoscopies in patients with a positive fecal occult blood testing[19]	The only quality indicator that has been shown to be directly associated with interval CRC Does not discriminate between subjects in whom the endoscopist detects one vs more than one adenoma Does not optimally differentiate between high- and low-performing endoscopists
Patient comfort and sedation	Routinely reporting and monitoring of patient comfort scores and sedation dosages[19,20]	Until recently no validated patient comfort score was available Not yet clear what patient comfort scores are considered acceptable The endoscopist, the nurse and the patient may have different opinions about the level of comfort during the procedure No gold standard regarding sedation during colonoscopy No validated score to assess the level of sedation during colonoscopy
Complication rate	Perforation in < 1:1000 colonoscopies[18-20] Post-polypectomy bleeding in < 1:100 colonoscopies with polypectomy[18,19]	Consensus based Complication rate is mainly dependent on the number of therapeutic colonoscopies, which may vary between screening strategies (colonoscopic screening of the entire population vs selection of high-risk individuals through fecal occult blood testing)

CRC: Colorectal cancer.