Validity of self-reported colorectal cancer test use in different racial/ethnic groups

Objective. Prevalence of colorectal cancer (CRC) screening is ascertained by self-reported screening, yet little is known about the accuracy of this method across different racial/ethnic groups, particularly Hispanics. The purpose of this study was to compare the accuracy of CRC self-report measures across three racial/ethnic groups. Methods. During 2004 and 2005, 271 white, African-American and Hispanic participants were recruited from a primary care clinic in Southeast Texas, and their CRC testing history based on self-report and medical record (the 'gold standard') were compared. Results. Over-reporting was prevalent. Overall, up-to-date CRC test use was 57.6% by self-report and 43.9% by medical record. Racial/ethnic group differences were most pronounced for Hispanics in whom sensitivity was significantly lower for any up-to-date testing, fecal occult blood testing, flexible sigmoidoscopy and double contrast barium enema. There were no statistically significant differences across groups for over-reporting, specificity or concordance. Conclusions. Self-report prevalence data are overestimating CRC test use in all groups; current measures are less sensitive in Hispanics.