Willingness to provide biologic samples: results from a healthy urban population of Mexicans and Mexican-Americans in Texas

Abstract

PURPOSE: To evaluate the willingness of participants in a population-based Mexican American cohort study to provide optional biologic samples during baseline recruitment. METHODS: Between July, 2001 and July, 2002, 1766 participants aged 13 88 who self-identified as Mexican or Mexican American were recruited using four methods of recruitment in Houston, Texas: random digit dial, intercept, blockwalk (or door-to-door), and network. Informed consent was administered and epidemiologic data were collected through an in-person interview. Participants were informed about the prospective nature of the study and given the option of providing one or more of the following biologic samples: blood, buccal cells, and/or urine. Participants could choose to provide no sample and still participate in the cohort study. RESULTS: Overall, 808 participants (46%) provided a blood sample, 1537 participants (87%) provided a buccal sample, 1048 participants (59%) provided a urine sample, and 1686 participants (96%) provided a DNA sample (either blood or buccal). Only 1% of all participants provided no sample at all. In examining the data by gender, women were more likely to provide a blood sample (47% vs. 43% in men) and less likely to provide a buccal sample (86% vs. 89% in men). There was no difference in their willingness to provide a urine sample (59% for both men and women). CONCLUSION: To our knowledge, this is the first study to evaluate the willingness of participants to provide a biologic sample in a population of healthy Mexicans and Mexican Americans living in the USA. Overall, the percentage of participants willing to provide optional samples was higher than anticipated in this underserved urban population, and there was little difference by gender. The most notable finding was that in participants over the age of 13, we were able to obtain samples suitable for DNA extraction from 96% of the study population.