possibility that experiences of prejudice and discrimination may have direct effects on health, which requires specific attention.
Stress is an important consequence of the experience of prejudice and discrimination. As suggested by Figure 2-1, stress can be treated as a separate factor, potentially mediating the effects on health not only of prejudice and discrimination, but also of other social and behavioral factors. It may, for instance, result from low socioeconomic status, and it may be alleviated by personal coping skills.
Figure 2-1 does not suggest any specific mechanisms to integrate the influences of all of these preceding factors on health. Relatively recently, various biopsychosocial mechanisms have been suggested that link environmental pressures, stress, psychological reactions, and physiological responses. While the investigation of these mechanisms has not so far focused strongly on racial and ethnic variation, the potential for insight into such differences merits separate discussion of this factor.
Health care is the final factor to consider. Several dimensions of care, as suggested above, might be relevant for differences: not only access to care, but also its quality; not only the behavior of health care providers, but also patient adherence to medical regimens; not only health care seeking behavior, but also self-care practices. While socioeconomic factors may be important in variations in health care use, other cultural factors specific to racial and ethnic groups, as well as geographic and other variation in health care, may also be involved.
All of these factors may operate at different points in the life course and also have direct effects on health in late life. The life-course perspective is discussed in the final chapter on factors. It is important for understanding late-life differences, many of which may have their origin in experiences early in life, perhaps in childhood or even infancy. A life-course perspective does not identify additional factors responsible for differences beyond those already noted, but it focuses on their operation at different stages in life and on the long-term effects. In discussing all the factors, therefore, we do not focus narrowly on their operation in late life but more broadly on their operation over the life course, with implications for late-life differences.
As the study of racial and ethnic differences in health has moved away from descriptive studies towards trying to identify the underlying determinants of these differences, researchers have naturally become increasingly interested in developing models of causal processes.
Establishing causality in the social sciences is very difficult at best and in some cases impossible. A basic constraint is that the effect of anything (but say, for example, a series of stressful events) on health cannot be