Voluntary Participation and Informed Consent to International Genetic Research

We compared voluntary participation and comprehension of informed consent among individuals of African ancestry enrolled in similarly designed genetic studies of hypertension in the United States and Nigeria. Survey questionnaires were used to evaluate factors associated with voluntariness (the number of people volunteering) and understanding of the study's genetic purpose. A total of 655 individuals (United States: 348; Nigeria: 307) were interviewed after participation in the genetic studies. Most US respondents (99%), compared with 72% of Nigerian respondents, reported being told the study purpose. Fewer than half of the respondents at both sites reported that the study purpose was to learn about genetic inheritance of hypertension. Most respondents indicated that their participation was voluntary. In the United States, 97% reported that they could withdraw, compared with 67% in Nigeria. In Nigeria, nearly half the married women reported asking permission from husbands to enroll in the hypertension study; no respondents sought permission from local elders to participate in the study. Our findings highlight the need for more effective approaches and interventions to improve comprehension of consent for genetic research among ethnically and linguistically diverse populations in all settings.