The remaining sample size for the analysis was

132,352. Characteristics of the 132,352 patients included in the analysis are enumerated in Table 1. It can be seen that 67% of the patients were women, and the mean (± standard deviation [SD]) age was 52.9 ± 16.7 years. Gross abnormalities such as scalloping and decreased folds accounted for less than 2% of all gross descriptions. Marsh I or II lesions were noted in 5944 individuals (4.5%), whereas Marsh IIIA was found in 819 (0.6%), and Marsh IIIB/C was found in 628 (0.5%). When a pathological diagnosis of CD was defined as blunted or flat villi (Marsh IIIA/B/C), a total of 1447 individuals (1.1%) were categorized as having CD. The most common number of small-bowel check details specimens submitted during upper endoscopy was

2 (histogram; Fig. 1). The mean (± SD) number of specimens submitted was 3.1 ± 1.6, and the median number submitted was 3. Of the 132,352 patients undergoing upper endoscopy with small-bowel biopsy, ≥4 small-bowel specimens were submitted in 45,995 patients RG7204 in vivo (35%). The proportion of patients with ≥4 specimens submitted during endoscopy increased from 33.8% in 2006 to 37.2% in 2009 (P for trend < .0001). Of the 45,995 individuals with ≥4 specimens submitted, Rolziracetam a pathologic diagnosis of CD was present in 824 (1.8%), whereas among the 86,357 patients in whom <4 specimens were submitted, CD was present in 623 (0.7%; P < .0001). When treated as a continuous variable, the number of specimens submitted was directly correlated with the probability of a pathologic diagnosis of CD ( Fig. 2). Biopsy of the duodenal bulb was performed in 10% of patients; inclusion of a bulbar biopsy was not associated with an increased

proportion of adherence to ≥4 small-bowel specimens (P = .4309), nor was it associated with an increased probability of a pathological diagnosis of CD (OR 0.93; 95% confidence interval [CI], 0.78-1.11; P = .4373). Patients with abnormal gross duodenal findings on endoscopy had an increased prevalence of CD (3.2% vs 0.7%; OR 4.64; 95% CI, 3.80-5.67). The relationship between adherence to the standard of ≥4 specimens submitted and a pathologic diagnosis of CD stratified by gross endoscopic findings is presented in Table 2. Gross endoscopic findings modified the association between number of specimens submitted and the prevalence of CD (Breslow-Day test for homogeneity of ORs: P = .0015). This relationship was greater for those with abnormal gross findings (OR 3.67; 95% CI, 2.86-4.72) than for those with normal gross findings (OR 1.91; 95% CI, 1.38-2.63).