is required in order to assess its impact on the population. Prevalence is obtained efficiently from a cross-sectional survey. The attributable risk for a range of risk factors is required in order to select interventions that will have the most powerful effect. Attributable risk is probably most efficiently obtained via the case-control strategy.
An even more recent frontier is the conceptualization of the age of onset for specific disorders. Determination of age of onset is required in order to time the intervention appropriately, that is, before the first incidence of a disorder or problem. Recognizing the importance of such data, the committee commissioned new analyses of data from the National Institute of Mental Health's Epidemiologic Catchment Area study (Robins and Regier, 1991). The conceptualizations and methods used in these analyses, and the resulting fresh perspectives they permit, are presented in Chapter 5.
Many scientific areas of study with links to prevention research have their origins in the behavioral and social sciences. Contributions from these areas that offer substantial leads for research on the prevention of mental disorders include the impact of psychological stress on health; the role of social support mechanisms in decreasing risk factors and enhancing protective factors; usage of health care delivery systems; the relationship between theoretical concepts such as attachment, self-esteem, and self-efficacy and later social relationships and health behaviors; the importance of social frames of reference, including race, culture, gender, and community context; and the relevance of developmental psychopathology in understanding individual patterns of adaptation over time.
There is an increasing tendency within the biological and behavioral sciences to appreciate the complexity and interplay of genetic and environmental interactions. There is also an increased recognition of the utility of a developmental focus. From this developmental focus has arisen the concept of sensitive periods, which is especially relevant to the timing of preventive interventions.
Whether a particular mental disorder and the risk factors associated with its onset warrant a major preventive research effort depends on a number of factors. In addition to information on incidence, prevalence, prodromal period, and age of onset, an understanding of the symptomatology, natural course, co-morbidity, and treatment effectiveness of the disorder is needed. For example, the incidence of a disorder will help determine the necessary size of the sample so that statistical analyses are