Health status by social class and/or minority status: implications for environmental equity research

Much of the epidemiologic research in the United States has been based only on the categories of age, sex and race; thus, race has often been used in health statistics as a surrogate for social and economic disadvantage. Few multivariate analyses distinguish effects of components of social class (such as economic level) from the relative, joint, and independent effects of sociocultural identifiers such as race or ethnicity. This paper reviews studies of social class and minority status differentials in health, with a particular emphasis on health status outcomes which are known or suspected to be related to environmental quality and conditions which increase susceptibility to environmental pollutants. Sociodemographic data are presented for the U.S. population, including blacks, Asian American/Pacific Islanders, American Indian/Alaska Natives, and Hispanics. Four areas of health status data are addressed: mortality, health of women of reproductive age, infant and child health, and adult morbidity. Conceptual and methodological issues surrounding various measures of position in the system of social strata are discussed, including the multidimensionality of social class, in the context of the importance of these issues to public health research. Whenever possible, multivariate studies that consider the role of socioeconomic status in explaining racial/ethnic disparities are discussed.