setting. The United States is only an average country in terms of the fraction of its residents who are foreign born, and increasing rates of international migration make this issue one that transcends borders.
Immigrants potentially offer some significant analytical advantages for understanding the origins of health disparities in any population. Most importantly, by definition immigrants have changed regimes, moving from an environment with one set of health risks, behaviors, and constraints into another one that may contain a quite different mix. Given the number of sending countries, the diversity of health regimes from which immigrants flow may be enormous. Because isolating meaningful variation in health environments can be problematic within a domestic-born population, scholars from several disciplines have been eager to use immigrant samples to measure the impact of environmental factors such as diet, health care systems, and environmental risks. But these perceived advantages of immigrant samples do not come without a cost, as immigrant samples also raise difficult analytical issues about the extent of health selectivity and the nature of the appropriate counterfactual.
This paper is divided into six sections. The first, section one, provides a simple descriptive comparison of some salient health outcomes of foreign-born and domestic-born Americans. Relying on the existing scientific literature, the section that follows highlights some key findings and the hypotheses these findings generate about the health status of the foreign-born population. Two of the more central questions that have emerged involve the mechanisms shaping health selectivity and the determinants of health trajectories following immigration. With this in mind, the next section outlines some simple theoretical models of health selectivity of immigrants and their subsequent health trajectories following immigration. The following section uses data from the New Immigrant Survey to provide new information on the diversity of health outcomes of new legal immigrants to the United States. New empirical models that estimate the determinants of health selectivity and health trajectories following immigration are presented in the next section. The final section summarizes our views on the principal research and public policy questions about immigrant health that are high priority. It also contains our recommendations about how scientific funding agencies may best assist the research community in answering these questions.
How do the native born and foreign born compare in terms of their overall health? Two widely used measures of health outcomes are self-reports of general health status based on a five-point scale ranging from