Parkinson’s Disease Questionnaire (PDQ-39)
A 39-item self-reported quality-of-life scale for Parkinson’s disease.
By Claire White
- Self-administered; approximately 15 minutes.
- 39 items across 8 domains: mobility, activities of daily living, emotional well-being, stigma, social support, cognition, communication, and bodily discomfort.
- Each item scored 0 to 4; domain scores standardised 0 to 100. Lower scores mean better quality of life.
- A summary index (PDQ-39 SI) is the average of all 8 domain scores.
What it measures
The PDQ-39 asks about the frequency of problems across 8 quality-of-life domains over the previous month. Mobility (10 items) covers walking and movement. Activities of daily living (6 items) covers self-care. Emotional well-being (6 items) covers mood. The remaining domains cover stigma, social support, cognition, communication, and bodily discomfort.
What the result tells you
Domain scores (0 to 100) and the summary index reflect health-related quality of life from the patient’s perspective. Lower scores indicate better quality of life. The PDQ-39 is sensitive to clinical change and is used as a patient-reported outcome in trials of symptomatic and neuroprotective therapies.
Used for
Evidence, psychometrics and provenance
Psychometrics
Reliability on a 0 to 1 scale. Higher is better.
References
This assessment uses a validated instrument and is reference information, not a diagnosis.