Positive predictive value and examiner variability in diagnosing duodenal ulcer.

The positive predictive value of a diagnosis of duodenal ulcer was studied in 255 patients with 274 ulcers diagnosed radiographically. Retrospective analysis of the radiographic examinations and correlation with endoscopy assessed examiner variability, ulcer size, duodenal bulb deformity, and the confidence level of the ulcer diagnoses. For all diagnoses, the overall positive predictive value was 57% with individual predictive values of 47%, 54%, and 70% among three examiners.

The radiologic detection of duodenal ulcers: effects of examiner variability, ulcer size and location, and technique.

Study of 91 endoscopically verified duodenal ulcers compared the effects of examiner variability, ulcer size and location, and radiographic technique on ulcer detection. Radiologic sensitivity of 61.5% was found for the entire group of 91 ulcers.

Predictive value of a diagnosis of colonic polyp on the double-contrast barium enema.

The positive predictive value of a diagnosis of colonic polyp on the double-contrast barium enema was determined by analyzing 160 polypoid lesions reported in 105 patients. Of the 160 polyps, 139 were confirmed by endoscopy, surgery, or repeat barium enema for a positive predictive value of 87%. Twenty-one lesions were not confirmed despite repeat endoscopy, repeat barium enema, review of the original study, or surgery, giving a false positive rate of 13%.

The utilization of xeroradiography for radiography of cross-section of thin cadaveric slices.

Although xeroradiography has had many medical applications, its utilization and the advantages it offers in the study of cadaveric sections has not previously been fully explored. It was our purpose to determine possible advantages or disadvantages this modality might have for this purpose. The edge enhancement which xeroradiography allows is a distinct advantage since the various anatomic structures become more clearly defined.