“…They have been demonstrated to be strong predictors of outcomes such as mortality (43, 7 3 , falls (71, 76, 87), institutionalization (43,75,95), and other health services utilization (60,95). Specific performance measures have been demonstrated to show improvement in response to interventions such as exercise (22) and cataract surgery (2), and to decline after hospitalization and with the onset of new health problems (82). Evidence has also been developed that performance measures can validly define a gradient of functioning even at the upper end of the functional spectrum (42,43,37,82), and are therefore able to assess the full range of functional status better than self-report measures, which mainly identify the presence of overt disability.…”