title: An assessment of occult blood testing to determine which patients with large bowel symptoms require urgent investigation.
abstract: One hundred and fifty-two consecutive patients with symptoms suggestive of colorectal disease were offered occult blood testing before undergoing barium enema examination or colonoscopy; one hundred and thirty-nine successfully completed the test. Thirty-four had positive results of whom thirteen had a cancer and eight an adenomatous polyp (diagnostic yield for neoplasia of 59 per cent). No false negative results occurred, a sensitivity of 100 per cent, and only 21 false positives occurred, a specificity for malignancy of 84 per cent. Subjects attending outpatients should be offered occult blood testing; those with a positive test should undergo colonoscopy. The cost-benefit of such a scheme is emphasized.
mesh_terms: D000368:Aged; D003108:Colonic Diseases / Q000175:diagnosis*; D003362:Cost-Benefit Analysis; D004739:England; D005189:False Positive Reactions; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009780:Occult Blood; D012002:Rectal Diseases / Q000175:diagnosis*; D013997:Time Factors