Continuous scale physical functional performance test: appropriateness for middle-aged adults with and without Parkinson's disease.

PURPOSE Functional measures are needed that are applicable to middle-aged adults with neurological disorders who are on the threshold of disability. One potential measure is the Continuous Scale Physical Functional Performance Test (CS-PFP), which has been normalized and validated to older adults but performance is unknown for adults younger than the age of 65 years with and without neurological disorders. The purposes of this investigation were (1) to compare scores on the CS-PFP of nondisabled adults in three age groups from 35 to 64 years with two groups of individuals older than the age of 65; (2) to determine whether there is a ceiling effect for nondisabled middle-aged adults; and (3) to determine whether performance of individuals in early stages of Parkinson's disease (PD) age 45 to 64 years differ significantly from performance of similarly aged nondisabled adults. METHODS Data were obtained from three samples: (1) 37 adults with PD (45-54 and 55-64 years; 57% female), (2) 70 nondisabled adults (35-44, 45-54, and 55-64 years; 69% female); (3) 72 nondisabled older adults (65-74 and 75-85 years; 79% female). The CS-PFP was administered in a single test session for each subject. Analysis of variance was performed for group differences with adjustment of sex as a covariate followed by a Student-Newman-Keuls post hoc analysis. RESULTS For nondisabled individuals, the CS-PFP total and domain scores were significantly lower in the oldest group (75-85 years) compared to all other age groups and significantly higher in the younger two groups (35-44 and 45-54 years) compared to the older groups. There was no ceiling effect for any domain score or total score for the adults younger than 65 years. For individuals with PD, both age groups had significantly lower scores on the CS-PFP than did the nondisabled counterparts. CONCLUSIONS Results from the nondisabled middle-aged individuals provide comparison data to be used clinically or in investigations of middle-aged adults with neurological dysfunction. Comparison of middle-aged individuals with PD to middle-aged nondisabled adults illustrates the true extent of functional difficulty experienced by individuals with PD and demonstrates the importance of using age appropriate comparison data. The CS-PFP is particularly applicable to middle-aged adults with compromised functional performance for their age but is too high to be effectively quantified with other assessment measures.