PROFILE PD: profile of function and impairment level experience with Parkinson disease--clinimetric properties of a rating scale for physical therapist practice.

BACKGROUND AND
PURPOSE: Individuals with Parkinson disease (PD) experience a range of deficits of body systems and activities. A clinical test is needed that is reliable, valid, applicable to physical therapist practice, and appropriate for use in early and mid-stages of the disease. PROFILE PD is one such scale, consisting of 24 items that would typically be assessed during the physical therapist's examination and evaluation of individuals with PD. The purpose of this article is to report on clinimetric properties of the PROFILE PD and to make the test available for use.
METHODS: Interrater reliability was determined using the intraclass correlation coefficient. Construct validity was determined by comparing scores on the PROFILE PD with the gold standard (Unified Parkinson's Disease Rating Scale [UPDRS]) as well as scales of physical activity and participation. Construct validity and structure of the PROFILE PD were further examined using exploratory factor analysis using principal component analysis with Promax rotation that allows a correlated factor structure.
RESULTS: Interrater reliability of the PROFILE PD was high (ICC = 0.97). Construct validity was demonstrated with the UPDRS (r = 0.86, P < 0.0001), Schwab & England Activities of Daily Living Scale (S&E) (r = -0.83, P < 0.0001), and Continuous Scale Physical Functional Performance test (r = -0.62, P < 0.0001). Principal component analysis demonstrated that the test comprises a single scale.
CONCLUSIONS: The PROFILE PD is a reliable and valid scale that can be used to quantify alterations in body systems and activity of individuals in early and mid-stages of PD. Use of the scale can provide an overall summary of the impact of PD on body systems and activities.