Physical performance measures in aging research.

Evaluation of physical functioning plays a valuable role in clinical geriatrics as well as in aging research. Physical functioning has generally been assessed through self- or proxy-report. An important addition to this form of assessment is the use of performance measures of physical function, in which individuals are asked to actually perform specific tasks and are evaluated using standardized criteria. Although there has been limited methodological work on physical performance instruments, this approach offers a number of potential advantages. Several performance assessments have been developed that correlate highly with other measures of health status and predict need for long-term care and mortality. It is suggested that more widespread use be made of physical performance assessments and that they be evaluated as measures of functioning in cross-national studies, as indicators of change in functioning over time, as endpoints in intervention studies, as tools for identifying persons functioning at high levels, and as sources of relevant information for the clinician.