need for a multidisciplinary approach that cuts across research domains. Recent demonstrations of the importance of cross-domain relationships—between health and retirement decisions, between economic status and health, between family structure and well-being in older age—support the contention that public policy must be guided by an understanding of the interplay among multiple factors. Initiatives in the United States, Europe, and Asia that integrate several salient domains of people's lives into single survey instruments have proven to be successful prototype data collection efforts. Examples of such endeavors include the Berlin Aging Study, the U.S. Health and Retirement Study (HRS), the Taiwan Study of the Elderly, the National Survey of Midlife Development in the United States, and the German Socio-Economic Panel. From their inception, these studies have included some or all of the following domains: income and wealth, labor force activity and retirement, health status (including biologic measurement) and utilization of health care facilities, cognition, and intergenerational transfers. The panel believes these models can be (and in some cases have been) successively adapted and used in many countries, both more and less industrialized.
It is the panel's conviction that the optimum way to develop both the research agenda and the data needed to address the economic and social issues associated with an aging world is through ongoing interaction among multidisciplinary national scientific communities. We believe extended interaction among sociologists, economists, demographers, epidemiologists, social psychologists, and statisticians is essential to (1) the creation and refinement of harmonized measures (conceptually comparable across societies) needed to understand outcomes such as labor force participation, health and disability status, complex family relationships, and economic status; and (2) the development of databases that can maximize the potential of cross-country and cross-time research for identifying the determinants of critical outcome variables. To deal effectively with differences among countries in policies, institutions, and incentive structures, it is equally essential that the multidisciplinary dialogue be driven by appropriate theories and models and that the data requirements of these theories and models be the main criteria used to select the empirical content of studies on aging populations.
It is important to stress that potential gains will not be realized unless there is a continuing and effective dialogue between the policy community and researchers, leading to the design of a program of data collection that can properly inform policy makers. This dialogue must be ongoing since many of the key dimensions of population aging can be expected to shift as socioeconomic circumstances change.