Continuous-scale physical functional performance in healthy older adults: a validation study.

ABSTRACT

OBJECTIVE: The continuous-scale physical functional performance test (CS-PFP) is an original instrument designed to provide a comprehensive, in-depth measure of physical function that reflects abilities in several separate physical domains. It is based on a concept of physical function as the integration of physiological capacity, physical performance, and psychosocial factors. SETTING: The test was administered under standard conditions in a hospital facility with a neighborhood setting. The CS-PFP consists of a battery of 15 everyday tasks, ranging from easy to demanding, that sample the physical domains of upper and lower body strength, upper body flexibility, balance and coordination, and endurance. Participants are told to work safely but at maximal effort, and physical functional performance was measured as weight, time, or distance. Scores were standardized and scaled 0 to 12. The test yields a total score and separate physical domain scores. DESIGN: The CS-PFP was evaluated using 148 older adults-78 community dwellers, 31 long-term care facility residents living independently, and 39 residents with some dependence. MAIN OUTCOME MEASURES: Maximal physical performance assessment included measures of maximal oxygen consumption (VO2max), isokinetic strength, range of motion, gait, and balance. Psychosocial factors were measured as self-defined health status using the Sickness Impact Profile (SIP), self-perceived function using the Health Survey (SF36), and Instrumental Activities of Daily Living (IADL). RESULTS: IADL scores were not significantly different among the groups. Test-retest correlations ranged from .84 to .97 and inter-rater reliability from .92 to .99 for the CS-PFP total and 5 domains. Internal consistency was high (Cronbach's alpha, .74 to .97). Both total and individual domain CS-PFP scores were significantly different for the three groups of study participants, increasing with higher levels of independence, supporting construct validity. CS-PFP domain scores were significantly correlated with measures of maximal physical performance (VO2max, strength, etc) and with physical but not emotional aspects of self-perceived function. CONCLUSION: The CS-PFP is a valid, reliable measure of physical function, applicable to a wide range of functional levels, and having minimal floor and ceiling effect. The total and physical domains may be used to evaluate, discriminate, and predict physical functional performance for both research and clinical purposes.