often more difficult to design and conduct successfully than unidisciplinary research.
Increasing the body of data based on longitudinal studies: Much of the available information on aging is based on crosscohort studies that compare individuals of different age groups. Although these studies provide some perspective on the effects of aging, they are subject to a number of non-age-related influences, such as secular and cohort effects. Longitudinal studies in which serial prospective measures are made on the same individuals over time provide a much more robust approach to gerontologic and geriatric research. Longitudinal studies, although inherently more time-consuming and expensive than crosscohort studies, are relevant to all domains of research—from basic science through clinical investigation to health services research.
Developing research resources—databases, well-defined study populations, cell lines, animal colonies, and animal models for research on aging: Such research resources often can be used by many different investigators conducting various studies at the same time. Federal and, in some cases, foundation funds can be brought to bear to establish such resources. Increasing attention must be given to the types of resources needed to promote the development of aging research to its next level of accomplishment.
Areas of neglect—gender, race, cultural background, and ethnicity: Substantial increases in research on aging in members of different racial, cultural, and ethnic groups are needed to clarify the mechanisms underlying differences in the presentation, course, and sequelae of a variety of geriatric-related disorders. Additionally, gender has been shown to have a major influence on biological as well as social and behavioral aspects of aging.
Importance of a life-course perspective: Substantial disability and health care expenditures in old age are rooted in the lifestyle, environmental, and other psychosocial factors that begin during youth or middle age. A developmental life-course perspective should be increasingly incorporated into aging research.
Emphasis on studying basic mechanisms of aging: Throughout its first phase of development, most gerontologic and geriatric research was descriptive in nature. Studies of the mechanisms of age-related alterations that build on this information and the expanded application of the new and powerful investigative techniques now available are needed.
Specialized health promotion and disease prevention research in older populations: A revolutionary increase in life expectancy has occurred already. A corresponding increase in active life expectancy