Evaluation of the Dutch version of the Parkinson's Disease Questionnaire 39.
Marinus J., Visser M., Jenkinson C., Stiggelbout AM.
The psychometric properties of the Dutch version of the Parkinson's disease questionnaire 39 (PDQ39-DV) were tested in 177 patients with Parkinson's disease (PD). Internal consistency of 7 of the 8 scales was adequate (>or=0.70), but was insufficient for 'bodily discomfort' (0.59). Correlation between the PDQ39 and other instruments in this study, the SCOPA-psychosocial questionnaire, Euroqol-5D, hospital anxiety and depression scale, and a visual analogue scale for quality of life, were 0.82, 0.74, 0.63 and -0.54, respectively. The factor analysis yielded 8 factors, which accounted for 65% of the variance and revealed only small differences with the original UK version. We conclude that the PDQ39-DV displays satisfactory psychometric properties and is an appropriate instrument to assess quality of life in Dutch patients with PD.