Test-retest reliability of the physical performance test for persons with Parkinson disease.
OBJECTIVE
Reliable measures are needed to document functional status and disease progression for people with Parkinson disease (PD). We, therefore, evaluated the reliability of the Physical Performance Test (PPT) for people with PD.


METHODS
Fourteen community-dwelling subjects with PD participated: 8 males, 6 females; modified Hoehn and Yahr Stages 2 and 2.5; mean age 62.4 years (+6.3). The test was administered twice, 1 week apart. The 7-item and 9-item summary scores of the PPT were each compared between sessions using repeated measures analysis of variance (ANOVA). The intraclass correlation coefficient (ICC) and method error (ME) were calculated to further assess reliability.


RESULTS
Between sessions, 7- and 9-item summed scores were not statistically different. The range of summed scores fell in the midst of the available score range for both the 7- and 9-item tests suggesting resistance to floor and ceiling effects. The ICCs showed good agreement (7-item = 0.818; 9-item = 0.895) indicating test reliability for this population. Based on the ME, an examiner can expect a 6% variation for the 7-item summary score and a 4% variation for the 9-item score summary between testing sessions.


CONCLUSIONS
The 7- and 9-item PPTs were demonstrated to be reliable objective measures in individuals with PD. Simple props and brief administration time (10-15 minutes) make the test practical to use.
Paschal
Karen
K
Department of Physical Therapy, Creighton University, 2500 California Plaza, Omaha, NE 68178, USA. kpaschal@creighton.edu
Oswald
Amber
A
Siegmund
Robert
R
Siegmund
Susan
S
Threlkeld
A Joseph
AJ
D000203:Activities of Daily Living; D000368:Aged; D004185:Disability Evaluation; D018450:Disease Progression; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000503:physiopathology*; D015203:Reproducibility of Results