ARTICLE Continuous Scale Physical Functional Performance Test: Appropriateness for Middle-Aged Adults With and Without Parkinson’s Disease Thomas M. Hearty, DPT, Margaret L. Schenkman, PT, PhD, Wendy M. Kohrt, PhD, and M. Elaine Cress, PhD 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 perfor- mance 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. Key words: Continuous Scale Physical Functional Performance Test, middle-aged adults, Parkinson’s disease (JNPT 2007;31: 64–70) INTRODUCTION O ne of the challenges for physical therapists is to dem- onstrate changes in function when working with middle- aged individuals who have early and subtle functional limi- tations resulting from neurological disorders. For adults younger than the age of 65 with progressive conditions such as multiple sclerosis (MS) or Parkinson’s disease (PD), it is important to measure meaningful changes in functional per- formance in the beginning stages of the disorder. Assessing change is particularly problematic when the individual has subtle difficulties with function, but still performs near the ceiling for typical functional measures (eg, Timed Up and Go, 1 Six Minute Walk test 2 ). One functional test, the Continuous Scale Physical Performance Test (CS-PFP), was developed to accurately assess functional limitations of older adults across a broad range of functional ability. 3 The test is reliable, valid, and sensitive to change for older community-dwelling adults with and without overt disability. 3–5 The utility of the CS-PFP has been demonstrated for evaluating older individuals who have preclinical disability, meaning that there are subtle indicators of disability, but the person can still function at a high level. This test has potential for use with middle-aged adults (ie, 35– 64 years) who have chronic conditions such as traumatic brain injury and fibromyalgia 6,7 or who are in early stages of degenerative disorders such as MS and PD. The CS-PFP is particularly attractive for use with these middle-aged adults on the threshold of disability because of the high sensitivity to change that has been previously demonstrated for older adults. However, it has not yet been established that the School of Medicine (T.M.H.), Physical Therapy Program, Department of Physical Medicine and Rehabilitation (M.L.S.), Division of Geriatrics (W.M.K.), University of Colorado Health Science Center, Denver, Col- orado; and Department of Exercise Science (M.E.C.), University of Georgia, Athens, Georgia. This project was supported in part by grants from the National Institutes of Health, # R01 HD043770-04 and MO1 #RR00051. Address correspondence to: Thomas Hearty, E-mail: thearty@yahoo.com Copyright © 2007 by Lippincott Williams & Wilkins ISSN: 1557-0576/07/3102-0064 DOI: 10.1097/NPT.0b013e3180676afa JNPT • Volume 31, June 2007 64