Latinas and breast cancer outcomes: population-based sampling, ethnic identity, and acculturation assessment

Latinas and African-Americans with breast cancer, especially those of lower socioeconomic status and acculturation, have been underrepresented in studies assessing treatment satisfaction, decision-making, and quality of life. A study was designed to recruit a large and representative sample of these subgroups.

Incident cases were selected by rapid case ascertainment (RCA) in the Los Angeles Surveillance, Epidemiology, and End Results Registry from 2005 to 2006, with oversampling of Latinas and African-Americans. Patients were mailed a questionnaire and $10 incentive 5 to 6 months after diagnosis; nonrespondents were contacted by telephone. Multivariate analysis was used to assess possible response bias. The RCA definition of Hispanic origin was validated by self-reports. The Short Acculturation Scale for Hispanics index for Latina respondents was used.

One thousand six hundred and ninety-eight eligible breast cancer cases were selected and 1,223 participated, for a response rate of 72.0%, which varied little by race/ethnicity. Age, race/ethnicity, and clinical factors were not associated with response; however, respondents were slightly more likely to be married and from higher socioeconomic status census tracts than nonrespondents. The RCA definition of Hispanic identity was highly sensitive (94.6%) and specific (90.0%). Lower acculturation was associated with lower education and literacy among Latinas.

High response rates among all subgroups were achieved due to the use of RCA, an incentive, extensive telephone follow-up, a native Spanish-speaking interviewer, and a focused questionnaire. The low acculturation index category identified a highly vulnerable subgroup. This large sample representing subgroups with greater problems will provide a basis for developing better interventions to assist these women.