Validation of the Finnish Version of the Unified Dyskinesia Rating Scale

Valtteri Kaasinen; Filip Scheperjans; Mikko Kärppä; Jaana Korpela; Anna Brück; Jussi O T Sipilä; Juho Joutsa; Juha Järvelä; Johanna Eerola-Rautio; Mika H Martikainen; Katja Airaksinen; Glenn T Stebbins; Pablo Martinez-Martin; Christopher G Goetz; Jeffrey Lin; Sheng Luo; Eero Pekkonen

doi:10.1159/000517369

Validation of the Finnish Version of the Unified Dyskinesia Rating Scale

Eur Neurol. 2021;84(6):444-449. doi: 10.1159/000517369. Epub 2021 Jul 14.

Authors

Valtteri Kaasinen^{1

2}, Filip Scheperjans³, Mikko Kärppä⁴, Jaana Korpela^{1

2}, Anna Brück^{1

2}, Jussi O T Sipilä^{1

2

5}, Juho Joutsa^{1

2

6}, Juha Järvelä⁷, Johanna Eerola-Rautio³, Mika H Martikainen^{1

2}, Katja Airaksinen^{1

2}, Glenn T Stebbins⁸, Pablo Martinez-Martin⁹, Christopher G Goetz⁸, Jeffrey Lin¹⁰, Sheng Luo¹¹, Eero Pekkonen³

Affiliations

¹ Department of Clinical Medicine, Clinical Neurosciences, Faculty of Medicine, University of Turku, Turku, Finland.
² Neurocenter, Turku University Hospital, Turku, Finland.
³ Department of Neurology, Helsinki University Hospital and Department of Clinical Neurosciences (Neurology), University of Helsinki, Helsinki, Finland.
⁴ Research Unit of Clinical Neuroscience, University of Oulu and Medical Research Center, Oulu University Hospital, Oulu, Finland.
⁵ Department of Neurology, Siun Sote North Karelia Central Hospital, Joensuu, Finland.
⁶ Turku Brain and Mind Center, University of Turku, Turku, Finland.
⁷ Turku City Hospital, Turku, Finland.
⁸ Department of Neurological Sciences, Rush University Medical Center, Chicago, Illinois, USA.
⁹ Center for Networked Biomedical Research in Neurodegenerative Diseases (CIBERNED), Carlos III Institute of Health, Madrid, Spain.
¹⁰ Department of Biostatistics and Data Science, University of Texas Health Science Center at Houston, Houston, Texas, USA.
¹¹ Department of Biostatistics and Bioinformatics, Duke University, Durham, North Carolina, USA.

PMID: 34261060
DOI: 10.1159/000517369

Abstract

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.

Keywords: Dyskinesia; Parkinson’s disease; Unified dyskinesia rating scale.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Dyskinesias*
Finland
Humans
Language*
Severity of Illness Index
Translations