OBJECTIVES: To develop a simple measure for quantification of the disability (dependency) due to Parkinson's disease (PD). PATIENTS: 65 nondemented PD outpatients, stage 1 to 5 of the Hoehn and Yahr Classification (HY). ASSESSMENT: HY, Schwab and England Scale, Northwestern University Disability Scale, Columbia University Rating Scale, Webster Scale, Barthel's Index, finger tapping, and timed "Up & Go" test. Six items from the ADL Section of the Unified PD Rating Scale (UPDRS)--as representative of the most basic ADL--were chosen to compose the UPDRS disability score (UDS), that was simultaneously rated by three observers. Global evaluations of disability by patient and physician were also recorded. STATISTICS: Descriptive, Cronbach alpha, kappa of Fleiss, Spearman rank correlation coefficients, Kruskal-Wallis test, and factor analysis. RESULTS: Internal consistency (Cronbach alpha = 0.86-0.87) and interobserver reliability (kappa = 0.84-0.98) were satisfactory. Convergent validity of the UDS with the applied PD rating scales (R = 0.76-0.92), global evaluations (R = 0.84-0.88), and timed tests (R = 0.47-0.65) was highly significant (all, p < 0.001). Distribution of UDS values across the HY categories showed significant trends (Kruskal-Wallis test, p < 0.001). A single factor explaining over 64% of the variance was identified. CONCLUSION: A simple and valid instrument for standardized evaluation of disability in PD is embedded in the UPDRS.
OBJECTIVES: To develop a simple measure for quantification of the disability (dependency) due to Parkinson's disease (PD). PATIENTS: 65 nondemented PD outpatients, stage 1 to 5 of the Hoehn and Yahr Classification (HY). ASSESSMENT: HY, Schwab and England Scale, Northwestern University Disability Scale, Columbia University Rating Scale, Webster Scale, Barthel's Index, finger tapping, and timed "Up & Go" test. Six items from the ADL Section of the Unified PD Rating Scale (UPDRS)--as representative of the most basic ADL--were chosen to compose the UPDRS disability score (UDS), that was simultaneously rated by three observers. Global evaluations of disability by patient and physician were also recorded. STATISTICS: Descriptive, Cronbach alpha, kappa of Fleiss, Spearman rank correlation coefficients, Kruskal-Wallis test, and factor analysis. RESULTS: Internal consistency (Cronbach alpha = 0.86-0.87) and interobserver reliability (kappa = 0.84-0.98) were satisfactory. Convergent validity of the UDS with the applied PD rating scales (R = 0.76-0.92), global evaluations (R = 0.84-0.88), and timed tests (R = 0.47-0.65) was highly significant (all, p < 0.001). Distribution of UDS values across the HY categories showed significant trends (Kruskal-Wallis test, p < 0.001). A single factor explaining over 64% of the variance was identified. CONCLUSION: A simple and valid instrument for standardized evaluation of disability in PD is embedded in the UPDRS.
Authors: Christopher I Higginson; Kimberly Lanni; Karen A Sigvardt; Elizabeth A Disbrow Journal: J Clin Exp Neuropsychol Date: 2013-05-13 Impact factor: 2.475