Trials in Minority Populations

It is a widely held belief that race is a biological categorization. This is not true. Indeed, race encompasses a broad group of people and is a socio-political categorization. There is biologic genetic diversity (genetic differences) within populations, when populations are defined by race, area of geographic origin, or ancestry. Race is complicated by admixture such that racial self-identity often does not correlate with genetic ancestry. While race does not matter biologically, it does matter sociopolitically. Race often correlates with exposures that can cause disease. Certain populations as defined by race are also less likely to receive quality care. The NIH Revitalization Act of 1993 requires NIH-funded research include racial minorities and women such that “valid subset analyses” can be done to distinguish differences. The implementation of the law has stimulated a movement encouraging minority accrual and a focus on assessment of differences in outcomes by race. The Federal rules imply that biologic racial differences account for differences in outcomes. What is needed is diversity of enrollment in clinical trials and open mindedness in assessment and interpretation of data. Populations should be defined with attention to distribution of genetic markers. Some scientific study should be targeted to specific populations as defined by those genetic markers. In certain instances, clinical trials with diverse populations can be assessed in meta-analysis, and some differences in metabolism of disease can be found. It is more useful to try to associate these differences with the area of geographic origin or ancestry versus race.