Validation of the Portuguese MDS-UPDRS: Challenges to Obtain a Scale Applicable to Different Linguistic Cultures

Mov Disord Clin Pract. 2025 Jan;12(1):34-42. doi: 10.1002/mdc3.14236. Epub 2024 Oct 26.

Abstract

Background: The MDS-UPDRS has been available in English since 2008, showing satisfactory clinimetric results and being proposed as the new official benchmark scale for Parkinson's disease (PD), being cited as a core instrument for PD in the National Institutes of Neurological Disorders and Stroke Common Data Elements program. For this reason, the MDS created guidelines for development of MDS-UPDRS official, clinimetrically validated translations.

Objective: This study presents the formal process used to obtain the officially approved Portuguese version of the MDS-UPDRS.

Methods: The study consisted of three phases: (1) Independent translation by Portuguese and Brazilian teams followed by a challenging consensus process that this article particularly emphasizes; (2) Cognitive pretest involving raters and patients from both Portugal and Brazil; (3) Validation test with a sample of 367 native Portuguese-speaking PD patients.

Results: The overall factor structure of the Portuguese version was consistent with the English version based on a comparative fit index ≥0.96 for all four parts of the MDS-UPDRS.

Conclusion: This version can be designated as the official Portuguese version of the MDS-UPDRS.

Keywords: Clinimetrics; MDS‐UPDRS; Parkinson's disease; rating scale; validation.

Publication types

  • Validation Study

MeSH terms

  • Aged
  • Brazil
  • Female
  • Humans
  • Male
  • Middle Aged
  • Parkinson Disease* / diagnosis
  • Portugal
  • Psychometrics / methods
  • Reproducibility of Results
  • Severity of Illness Index
  • Translations