A1 Refereed original research article in a scientific journal
Validation of the Finnish Version of the Unified Dyskinesia Rating Scale
Authors: Kaasinen Valtteri, Scheperjans Filip, Kärppä Mikko, Korpela Jaana, Brück Anna, Sipilä Jussi OT, Joutsa Juho, Järvelä Juha, Eerola-Rautio Johanna, Martikainen Mika H, Airaksinen Katja, Stebbins Glenn T, Martinez-Martin Pablo, Goetz Christopher G, Lin Jeffrey, Luo Sheng, Pekkonen Eeero
Publisher: KARGER
Publication year: 2021
Journal: European Neurology
Journal name in source: EUROPEAN NEUROLOGY
Journal acronym: EUR NEUROL
Volume: 84
Issue: 6
First page : 444
Last page: 449
Number of pages: 6
ISSN: 0014-3022
DOI: https://doi.org/10.1159/000517369
Introduction:
The Unified Dyskinesia Rating Scale (UDysRS) was developed to provide a comprehensive rating tool of dyskinesia in Parkinson’s disease (PD). Because dyskinesia therapy trials involve multicenter studies, having a scale that is validated in multiple non-English languages is pivotal to international efforts to treat dyskinesia. The aim of the present study was to organize and perform an independent validation of the UDysRS Finnish version.
Methods:
The UDysRS was translated into Finnish and then back-translated into English using 2 independent teams. Cognitive pretesting was conducted on the Finnish version and required modifications to the structure or wording of the translation. The final Finnish version was administered to 250 PD patients whose native language is Finnish. The data were analyzed to assess the confirmatory factor structure to the Spanish UDysRS (the reference standard). Secondary analyses included an exploratory factor analysis (EFA), independent of the reference standard.
Results:
The comparative fit index (CFI), in comparison with the reference standard factor structure, was 0.963 for Finnish. In the EFA, where variability from sample to sample is expected, isolated item differences of factor structure were found between the Finnish and Reference Standard versions of the UDysRS. These subtle differences may relate to differences in sample composition or variations in disease status.
Conclusion:
The overall factor structure of the Finnish version was consistent with that of the reference standard, and it can be designated as the official version of the UDysRS for Finnish speaking populations.