Translation and validation of the standard Chinese version of PDQ-39: a quality-of-life measure for patients with Parkinson's disease.

PDQ-39 has been widely used in the research and clinical management of Parkinson's disease. It has been translated into and validated in various non-English languages. We report here on the validity and reliability results for the translated standard Chinese PDQ-39 questionnaire. Fifty-four patients were recruited from a movement disorder clinic and two regional patient groups, and data were collected by direct interview. Nineteen patients had the tests repeated 4 weeks later to assess the test-retest and interrater reliability. The standard Chinese version of PDQ-39 demonstrated acceptable internal consistency (Cronbach's alpha = 0.54-0.90) and was comparable to versions in other languages. Further analysis showed good construct validity and test-retest reliability. Implications and limitations of the study are discussed.