Printed In U SA. Longitudinal Compliance with Annual Screening for Fecal Occult Blood

In a randomized, controlled trial of fecal occult blood screening for colorectal cancer, the Minnesota Colon Cancer Control Study carried out 11 annual mail screens in two phases between 1976 and 1992. This long-term compliance record of 15,476 individuals is summarized and related to demographic charactenstics as well as to the screening experience of the participants. There was a strong and consistent effect of age, with peak compliance among participants about 70 years old, and lower compliance among the youngest (s55 years) and oldest (>80 years) participants. There was a significantly higher rate of screen compliance among participants who lived with other participants, compared with households where only one individual partici-pated in the study. Finally, participants who underwent a diagnostic colorectal examination with negative results had significantly lower odds of compliance. Am J Epidemiol 1995;142:176-82. colonic neoplasms; cooperative behavior; mass screening; prospective studies Colorectal cancer continues to account for about 10 percent of all deaths from cancer in the United States (1). Because methods for primary prevention remain unknown, there has been widespread interest in screening for early colorectal cancer, particularly by testing for fecal occult blood. This test, using guaiac-impregnated paper slides, can be completed at home and returned by mail. The efficacy of long-term annual screening by mail was recently established by the Minnesota Colon Cancer Control Study, which found that annual screening for fecal occult blood decreased 13-year cumulative mortality from colorectal cancer by 33 percent (2). One other large-scale controlled trial of screening by mail has been completed in New York (3), while four other trials are currently proceed