If You Have a Low Adenoma Detection Rate, Don’t Blame Your Fellows

Quality measures in colonoscopy are at the forefront in the field of gastroenterology, particularly in light of the current emphasis on ‘‘accountable’’ care. Colonoscopy quality measures include cecal intubation rate, complication rate, adenoma detection rate (ADR), and appropriate screening and surveillance intervals. For screening and surveillance colonoscopy, ADR is emerging as perhaps the most important quality indicator, since identification and removal of adenomas is the primary goal. Factors that improve ADR include adequacy of bowel preparation, cecal withdrawal time, time of day that colonoscopy is performed, type of sedation regimen used, and use of techniques such as cap-assisted colonoscopy and retroflexion in the right colon [1, 2]. Whether fellow involvement in colonoscopy affects ADR, the subject of the paper by Oh et al. [3] in this issue of Digestive Diseases and Sciences, has been less well studied. Most endoscopists who train fellows to perform colonoscopy probably have an opinion, based on personal experience, about whether fellow involvement increases or decreases ADR. Oh et al. looked at the issue more objectively by performing a meta-analysis of relevant studies to determine if a difference in polyp detection rate (PDR) or ADR occurs when a fellow is involved in colonoscopy. On the one hand, it might seem intuitive that PDRs and ADRs would be higher with a fellow and attending both observing the same procedure, as dual observers increase ADR [4]. Additionally, since fellows tend to take longer to complete a colonoscopy, one might infer that increased cecal withdrawal time by a fellow is associated with an increased ADR, similar to the data showing increased ADR with increased cecal withdrawal time amongst attending endoscopists. On the other hand, one might predict a lower ADR with fellows due to other factors, such as rapid withdrawal through colon segments when the fellow is having difficulty managing the colonoscope, a less thorough examination of the back surfaces of colonic folds, and inability to retroflex the colonoscope in the right colon. The impact, if any, of fellow participation on the PDR and ADR is important information for clinicians who regularly train fellows, particularly if ADR is recorded and/ or reported as a quality indicator. Although PDR is not relevant for determining screening and surveillance intervals, calculating PDR is much simpler since polyp histology is not required. If PDR correlates with ADR, some programs may choose to monitor PDR as a useful metric as fellows progress through training, allowing an objective assessment of fellow proficiency. Additionally, there may be patients who receive care at training institutions who want to know whether having a trainee involved affects the quality of their medical care. To determine if fellow involvement in colonoscopy affects ADR, Oh et al. [3] performed a comprehensive literature search, identifying articles in which the ADR, as well as the percent of colonoscopies, involving fellows was reported. From this information, they applied a modified Quality Assessment of Diagnostic Accuracy Studies (QUADAS) tool to the data to determine the impact of fellow participation in colonoscopy on ADR. A total of 14 studies met inclusion criteria, accounting for 21,504 colonoscopies. Based on the combined data, the RR (95 % CI) for detecting polyps when a fellow was present was 1.04 (0.94, 1.15), and for detecting adenomas was 1.03 (0.93, 1.14) suggesting that fellow involvement has no impact on D. S. Early (&) Department of Medicine, Washington University in St. Louis, 660 South Euclid Avenue, Campus Box 8124, St. Louis, MO 63110, USA e-mail: dearly@dom.wustl.edu