[Comparative study of x-ray and endoscopy in the detection of polyps and cancer of the large bowel with office computer]

A comparative study of X-ray and endoscopy in the detection of polyp and cancer of the large bowel was done with the use of office computer, and following result was obtained. False positive and negative rate of X-ray in the detection of polyp was 31.5% and 16.3% respectively when X-ray preceded endoscopy. False negative rate of X-ray and endoscopic diagnosis was 40.8% and 28.6% respectively in the detection of polyp, when endoscopy preceded X-ray. But the possibility that the false negative of endoscopy might be the false positive of X-ray was not excluded in many cases. The false positive and negative rate of X-ray diagnosis was 21.0% and 7.0% respectively in the detection of cancer when X-ray preceded endoscopy. The false negative rate of X-ray diagnosis was 2.8% in the detection of cancer when endoscopy preceded X-ray. It was emphasized that X-ray should be preceded by endoscopy in the detection of polyp and cancer of the large bowel in order to reduce the false positive and negative rate of X-ray diagnosis to the minimum.