Double-blind study of single and double contrast upper gastrointestinal examinations using endoscopy as a control.

A total of 100 patients were examined by both single and double contrast upper gastrointestinal radiography. The radiographs were coded, interpreted blindly by two gastrointestinal radiologists, and the accuracy of each examination was determined using endoscopy as the standard. The interpretation error rate for each type of examination alone was almost identical. Interpretations based on a combination of both studies significantly reduced both the false positive and negative errors and strongly suggests a complementary role for the two methods.