Background: The accuracy of a Barrett's esophagus diagnosis is not well studied.
Objective: Our purpose was to evaluate the accuracy of a clinical Barrett's esophagus diagnosis and the reproducibility of an esophageal intestinal metaplasia diagnosis.
Methods: All patients with a Barrett's esophagus diagnosis between 1994 and 2005 were identified by use of International Classification of Disease (ICD) and Systematized Nomenclature of Medicine (SNOMED) coding. Subsets received manual record review (endoscopy/pathology reports), slide review by a referral pathologist (interrater reliability), and 2 blinded reviews by the same pathologist (intrarater reliability).
Setting: An integrated health services delivery system.
Main outcome measurements: Accuracy of electronic clinical diagnosis and reproducibility of esophageal intestinal metaplasia diagnosis.
Results: A total of 2470 patients coded with Barrett's esophagus underwent record review; a subgroup (616) received manual pathology slide review. Review confirmed a Barrett's esophagus diagnosis for 1533 (61.9%) patients: 437 of 798 subjects (54.8%) with a SNOMED diagnosis alone, 153 of 671 subjects (26.8%) with an ICD diagnosis alone, and 940 of 1101 subjects (85%) who had both a SNOMED and an ICD diagnosis. The same metaplasia diagnosis occurred with 88.3% of subjects (original vs referral pathologist, interrater reliability; kappa = .42, 95% CI, 0.34-0.48). The referral pathologist made the same metaplasia diagnosis twice for a given patient for 88.6% of subjects (intrarater reliability, 2 reviews by same pathologist; kappa = 0.65, 95% CI, 0.35-0.93).
Limitations: The accuracy of a Barrett's esophagus diagnosis likely represents the minimum number, given the strict criteria.
Conclusions: A community pathologist's diagnosis of esophageal intestinal metaplasia is likely to be confirmed by a referral pathologist. Electronic diagnoses of Barrett's esophagus overestimate the prevalence, although they are usually confirmed in patients with both a SNOMED and ICD diagnosis of Barrett's esophagus.