Cross-cultural evaluation of the short form 8-item Parkinson's Disease Questionnaire (PDQ-8): results from America, Canada, Japan, Italy and Spain

Parkinsonism Relat Disord. 2007 Feb;13(1):22-8. doi: 10.1016/j.parkreldis.2006.06.006. Epub 2006 Aug 22.


Objective: The purpose of this study was to evaluate the psychometric properties of a short form health survey, the Parkinson's Disease Questionnaire (PDQ-8), cross-culturally, by comparing results gained from this instrument to the original longer form instrument-the PDQ-39.

Design: Data are from the Global Parkinson's Disease Survey.

Outcomes: The 8-item Parkinson's Disease Questionnaire Single Index Score (PDQ-8-SI). In this study, we evaluate response rate, scaling assumptions, and data quality, in terms of comparability of results with the parent form from which the PDQ-8 was derived, of the instrument in the USA, Canada, Spain, Italy and Japan.

Results: The PDQ-8 was found to produce results that were very similar to the parent form across all five countries. However, it should be borne in mind that the PDQ-8 was nested within the PDQ-39, and results may be influenced by this.

Conclusions: Results suggest that the PDQ-8 is a valid and reliable measure that can be appropriately and meaningfully used in cross-cultural studies.

Publication types

  • Comparative Study
  • Validation Study

MeSH terms

  • Aged
  • Canada
  • Cross-Cultural Comparison*
  • Female
  • Humans
  • Italy
  • Japan
  • Male
  • Parkinson Disease / psychology*
  • Quality of Life
  • Spain
  • Surveys and Questionnaires / standards*
  • United States