A RELIABILITY AND VALIDITY STUDY OF THE URDU VERSION OF THE UNIFIED PARKINSON DISEASE RATING SCALE
Introduction: In order to evaluate the severity and progression of Parkinson's disease, the Unified Parkinson Disease Rating Scale (UPDRS) is commonly used. An important aspect of any rating scale, including the UPDRS, is its reliability and validity.
Material & Methods: In this cross-sectional study, data were collected between October 2020 and January 2021. In accordance with standard guidelines for translating UPDRS into Urdu, 215 Parkinson's disease patients who met predefined inclusion criteria were administered the final Urdu version.Cronbach alpha was used to determine an inter-item correlation. A test-retest reliability analysis was conducted by comparing UPDRS-U scores at baseline and after two weeks. We also compared the scores of two observers in order to determine inter-rater reliability. Concurrent validity was established using the Spearman correlation coefficient.
Results: UPDRS-U had a Cronbach alpha score of 0.940, indicating internal consistency. The Spearman correlation coefficient for UPDRS-U composite scores at baseline and two weeks later was 0.82, suggesting excellent test-retest reliability.According to this study, UPDRS-U and BBS have good concurrent validity (rs =-.808, p=0.001) and UPDRS and ABC have good concurrent validity (rs =-.791, p=0.001). Furthermore, the two observers' UPDRS-U scores were positively correlated, with a spearman correlation coefficient of 0.97 and P< 0.001 indicating good inter-rater reliability. Correlations between individual item scores and the UPDRS total item score were found to range between 0.194 and 0.866.
Conclusion: UPDRS-U was found to be a reliable and valid tool for assessing Parkinson disease symptoms and progression among Pakistani adults.
Key Words: Outcome assessment, Parkinson’s disease, Reliability, UPDRS, Validity