This project will result in the standardization of an assessment of functional skills of older persons that will be used by occupational therapists for more accurate (a) determination of capacity for independent living, (b) identification of individuals at-risk for functional decline, and (c) selection of appropriate and cost-effective interventions. This psychometrically-sound and innovative evaluation tool, the Assessment of Motor and Process Skills (AMPS), provides an ecological appraisal of motor and process (cognitive) skills as they are used during the actual performance of a familiar, chosen, and relevant daily life task. A total of 30 tasks, 15 motor skill items, and 20 process skill items will be calibrated on a stratified sample of 200 younger well adults and 700 older adults selected to represent the well to frail elderly continuum, and with equal representation for gender, race (black/white), and diagnostic subgroup (well elderly, frail elderly, stroke, dementia, and hip fracture). In addition to careful examination of reliability and concurrent validity, the utility of the AMPS as a measure of change, and as a predictor of ability across tasks of greater or lesser difficulty and between home and clinical settings will be examined. The AMPS skill items are conceptualized as universal taxonomies of the motor and process operations that are necessary for skilled task performance. Evaluation of these operations represents a level of task analysis that is between typical approaches that evaluate discrete underlying constituents (e.g., strength or mental status evaluations), and those that evaluate global task performance (e.g., ADL/IADL indexes). The ability to simultaneously assess component motor and process skills as the person actually performs a daily living task links discrete and global methods in a manner that permits direct measurement of the impact of motor and process skill deficits on independent daily life task performance. The use of recently developed many-faceted Rasch analysis methods will lead to measures that adjust person scores to account for the severity of the rater and the difficulty of the tasks the person chooses to perform. Further, the use of many-faceted Rasch analysis will lead to the definition of a hierarchy of task and skill item difficulties, along a common linear continuum (scale), that can be used to compare and predict performance across tasks that are harder, or easier, than those the person actually performed. Knowledge of where along this conceptual ability continuum of skill items the person experiences difficulty, combined with the ability to estimate the point at which the person will encounter difficulty on an easier or more challenging task, will provide precise and critical information that is needed to plan and measure the efficacy of intervention programs. Finally, the assessment will be designed such that individuals of varying ability levels and from different subgroups (gender, racial/ethnic, diagnostic) can be compared on the same linear scale.
