The aim of this study was to compare responses to two interventions (personalized-form [PF] letter messages versus personalized-tailored [PT] letter messages) using medical record data for promoting appointment scheduling and screening for breast and cervical cancer among urban low-income women from three ethnic groups: African-American, Mexican-American, and non-Hispanic white women. The 1,574 women participating in the randomized controlled trial were assigned to one of three groups: (1) PF letter, (2) PT letter, (3) control (no letter). Logistic regression analyses show that (1) personalized-tailored letters containing individualized references to recipients' cancer risk factors failed to increase rates of recommended cancer screening behaviors, especially among non-Hispanic white women; and that (2) in contrast, a personalized-form letter with general breast and cervical cancer screening messages increased cancer screening rates in this population, especially among non-Hispanic white and Mexican-American women.