Our Study: Provider Level Variability in Colonoscopy Yield

Most readers of this blog will recognize that one focus has been on delivering high value medical care.  In pediatric gastroenterology, there is a great deal of variability in the use of endoscopy as a tool.  When there are individuals with high-use/low-value endoscopy, some might question whether this is due to training, expediency, financial motivation, or a lack of clinical confidence.

There have been a number of studies looking at diagnostic yield with pediatric colonoscopy but none on individual provider variation.   To look into this issue, we examined our outpatient experience with colonoscopy among 16 providers.  This work has now been published:

Digestive Diseases (Full Text): Diagnostic Yield Variation with Colonoscopy among Pediatric Endoscopists

Key points:

  • This study found high variability in diagnostic yield among the 16 clinicians ranging from as low as 22% to as high as 86% (p = 0.11) with an overall diagnostic yield of 48% for colonoscopy; excluding follow-up colonoscopies, the diagnostic yield was 42%.
  • Abnormal calprotectin and abnormal blood tests were associated with higher diagnostic yields of 83 and 65%, respectively, compared with symptoms such as diarrhea, and rectal bleeding which had yields of 43, and 61%.
  • Ileal intubation rates averaged 90% (range ­63–100%, p = 0.06). Ileal intubation is important because, among our patients with a normal colon, there were 21 (6%) with a grossly abnormal ileum and an additional 16 (4%) with abnormal histology in the ileum.  Thus, about 10% of patients with a normal endoscopic and histologic evaluation of the colon had abnormalities in the terminal ileum. A NASPGHAN report (JPGN 2017; 65: 125-31) on quality improvement recommended an ileal intubation rate of 90% as a goal.


  • Our group’s overall diagnostic yield is similar to previous studies which ranged from 33-64%.
  • Among physicians with the lowest and highest yield, there was not a specialized focus in IBD or functional GI disorders.  Thus, the driving factor for the variation in diagnostic yield is related to the threshold for performing an endoscopy in patients with probable functional disorders and the response to parental pressures.
  • A negative endoscopic study has not been shown to improve outcomes in patients with functional abdominal pain; though a normal colonoscopy would provide reassurance in some situations (eg. familial polyposis).

My take: Goals for pediatric endoscopy to provide high-value care could include ileal intubation rates of >90% and provider diagnostic yields of >40%.  High-value also includes the actual cost of the procedure; most of our outpatient endoscopies are performed in a pediatric ambulatory center with much lower costs than hospital-based endoscopy.

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