title: Turkish Version Study of "Parkinson's Disease Quality of Life Questionnaire" (PDQL).
abstract: BACKGROUND
  This study aimed to evaluate Turkish transcultural adaptation, reliability, and validity of "Parkinson's Disease Quality of Life Questionnaire" (PDQL), which has been developed to assess the quality of life of patients with Parkinson's disease.
  
  
  METHODS
  Eighty-nine patients who were included in the study were diagnosed with Parkinson's disease. They were presented to the outpatient clinic of the Istanbul Faculty of Medicine, Physical Medicine and Rehabilitation department between July 2005 and April 2008. The Turkish translated version of PDQL (PDQL-TR), "Unified Parkinson's Disease Rating Scale" (UPDRS), and Hoehn & Yahr (HY) were used as the main outcome measures.
  
  
  RESULTS
  The calculated Pearson correlation coefficient for PDQL, H&Y, and UPDRS ranged between -0.36 and -0.80. Cronbach's alpha coefficients of the PDQL-TR complete questionnaire and subdomains were higher than 0.80. The absolute value of item-total score correlation coefficients by Pearson fluctuated between 0.40 (question 4-total score) and 0.88 (question 26-total score), whereas the subdomain-total score correlation coefficients ranged between 0.81 and 0.96. PDQL-TR showed high stability according to the ICC results, ranging between 0.75 (Emotional Function) and 0.88 (Parkinsonian Symptoms).
  
  
  CONCLUSIONS
  The psychometric features of PDQL-TR are satisfactory, and our results are consistent with the previous literature findings. PDQL-TR is a valid and reliable tool to measure health-related quality of life in patients with Parkinson's disease.
authors.affiliation: Department of Physiotherapy and Rehabilitation, İstanbul Bilgi University School of Health Sciences, İstanbul, Turkey.
authors.forename: Elif Elçin
authors.initials: EE
authors.lastname: Dereli
authors.affiliation: Department of Physical Medicine and Rehabilitation, İstanbul University İstanbul Faculty of Medicine, İstanbul, Turkey.
authors.forename: Ayşe
authors.initials: A
authors.lastname: Yaliman
authors.affiliation: Department of Physiotherapy and Rehabilitation, Marmara University Faculty of Health Sciences, İstanbul, Turkey.
authors.forename: Tuğba
authors.initials: T
authors.lastname: Kuru Çolaka
authors.affiliation: Department of Physiotherapy and Rehabilitation, İstanbul Bilgi University School of Health Sciences, İstanbul, Turkey.
authors.forename: Aycan
authors.initials: A
authors.lastname: Çakmak
authors.affiliation: Department of Physiotherapy and Rehabilitation, İstanbul University Faculty of Health Sciences, İstanbul, Turkey.
authors.forename: Arzu
authors.initials: A
authors.lastname: Razak Özdinçler
authors.affiliation: Department of Physiotherapy and Rehabilitation, Yeditepe University Faculty of Health Sciences, İstanbul, Turkey.
authors.forename: Şule
authors.initials: Ş
authors.lastname: Badilli Demirbaş
keywords: Parkinson disease; quality of life; reliability; validity