The Effect of Fecal Occult-Blood Screening on the Incidence of Colorectal Cancer

To the Editor: Mandel and associates (Nov. 30 issue) 1 show that either annual or biennial fecal occult-blood testing significantly reduces the incidence of colorectal cancer. Their findings were primarily the result of using the equivalent of the rehydrated Hemoccult II card, a fecal occult-blood test that has good sensitivity but poor specificity and that is not currently recommended for use by its manufacturer (Beckman Coulter, Fullerton, Calif.). Thus, the results with the rehydrated Hemoccult II card cannot be used to support its use in routine clinical practice. The nonrehydrated Hemoccult II is the most widely used fecal occult-blood test in . . .