draws on information supplied by basic biomedical research, health services studies, and the behavioral and social sciences. Clinical research shares many techniques and subjects with other areas of investigation but has a special focus on the connections between organic illness and functional status and on specific interventions to treat or prevent organic diseases. Several recent Institute of Medicine (IOM) studies on research into the effectiveness and outcomes of health care have described the potential for interaction between clinical research and other areas of investigation in the study of older patients (IOM, 1989, 1990a).
In addition to overlapping with other areas of research, the clinical research priorities described below share a common opportunity for investigation—study of the value of rehabilitative care in clinical outcomes, in cost benefits, and in cost effectiveness.
The first priority is research into the causes, prevention, management, and rehabilitation of functional disability in elderly persons.
The overwhelming importance of functional capacity as a determinant of older persons' needs dictates a special focus on factors that limit the independence of elderly individuals. Increasingly, the clinical geriatric research community recognizes and agrees that it is well positioned to make significant short-term advances in the understanding of the physiologic and pathophysiologic mechanisms underlying the dependency and frailty that characterize the final stages of life.
Although at any given time, a majority of older persons are free of significant disability, the rate of disability rises with age. The National Health Interview Survey (National Center for Health Statistics, 1985) reported that 23 percent of all elderly persons are unable to perform at least one of the activities of daily living (ADLs). These ADLs include bathing, dressing, grooming, going to the toilet, being able to move from bed to chair, being continent, and being able to feed oneself. About half of those 85 years of age and older need assistance to perform one or more ADLs or to carry out one or more instrumental activities of daily living (IADLs). These include shopping, using public transportation, cooking, using the telephone, housekeeping, and managing finances (Dawson et al., 1987). In order for an older person to be independent, he or she must be able to perform these activities. Clearly, with increasing inability to per-