housing arena. A second window of opportunity can be found in new technologies for the mapping and identification of environmental “hot spots.” Geographic information systems (GISs) exploit technological advances in ways that are transforming how research is being conducted in the social sciences. For instance, data on health outcomes can now be linked virtually in real time to address-level data bases on employment, density of liquor stores, mixed land use, and building code violations. A principal advantage of GISs is community profiling and the ability to overlay multiple health-related phenomena (e.g., deaths, cancer clusters, and accident hot spots) in time and space.
Previous sections of this report discussed the importance of predisease pathways, but there is little research on how such pathways interact with community, environmental, and cultural contexts. Research on the collective properties of healthy communities thus needs to be integrated with the vigorous body of research on individual pathways. For example, do allostatic loads build up faster and in more destructive ways for racial/ethnic or cultural minorities living in some contexts than others? What are these environments? What mechanisms explain person-environment interactions? Are there threshold effects or leveling effects of the environment on disease risk such that individual factors become overwhelmed? What are these thresholds and for what aspects of the environment? As one example, there is evidence that race and income are not significant predictors of disease in areas of concentrated disadvantage (Yen and Syme, 1999). Multilevel studies share a unifying theme in stressing the interaction of individuals and context. Unfortunately, research has yet to systematically link validated measures of community context with the developmental course of predisease pathways and individual-level health outcomes. Although in its infancy, we believe that the multilevel study of developmental and community processes related to health is a crucial research frontier that deserves priority.
To be sure, health environments are not limited to geographical communities. As described elsewhere in this report, families, workplaces, religious institutions, and peer groups generate their own collective properties that bear on health. Many of these factors are in turn influenced by cultural context and background. Nonetheless, strong friendship ties and family social support networks have been found to promote individual health (Berkman and Syme, 1979). Nor are the relevant health environments