title: The PDQ-39 Spanish version: reliability and correlation with the short-form health survey (SF-36).
abstract: METHODS
  The Parkinson's Disease Questionnaire (PDQ-39) was the first specific instrument for evaluation of the "health-related quality of life" (QoL) in Parkinson's disease patients. The PDQ-39 has been subjected to adaptation to Spanish language and culture (PDQ-39 Spanish version, PDQ-39SV) and this version has been validated in aspects of internal consistency and construct validity. The present study assess the test-retest reliability and the convergent validity of the PDQ-39SV with a generic QoL instrument (SF-36).
  
  
  RESULTS
  Most of the PDQ-39 dimensions showed an adequate consistency-Cronbach's alpha > 0.7 for six dimensions. As a whole, test-retest reliability resulted satisfactory. Two dimensions-activities of daily living and emotional well-being- showed a low grade significant difference (paired Student t-test, p < 0.05) due to improvement in the second survey (at 10 to 14 days from the first one) perhaps related to adjustments of the treatment at the first visit. A strong association (Spearman r, p < 0.001), indicative of convergent validity, was obtained for the PDQ-39 dimensions and the relevant SF-36 scales, as well as for the physical and mental component summary scores of the SF-36.
  
  
  CONCLUSIONS
  Taking into account these results and previous studies, it is concluded that the PDQ-39 SV is a reliable measure that has construct validity.
authors.affiliation: Department of Neurology, Hospital Universitario de Getafe, Madrid, Spain. pmartinezm@meditex.es
authors.forename: P
authors.initials: P
authors.lastname: Martínez Martín
authors.forename: B
authors.initials: B
authors.lastname: Frades
authors.forename: F J
authors.initials: FJ
authors.lastname: Jiménez Jiménez
authors.forename: M
authors.initials: M
authors.lastname: Pondal
authors.forename: J J
authors.initials: JJ
authors.lastname: López Lozano
authors.forename: L
authors.initials: L
authors.lastname: Vela
authors.forename: A
authors.initials: A
authors.lastname: Vázquez
authors.forename: J
authors.initials: J
authors.lastname: del Val Fernández
authors.forename: M
authors.initials: M
authors.lastname: Diví
authors.forename: N
authors.initials: N
authors.lastname: Fabregat
authors.forename: A
authors.initials: A
authors.lastname: Tuldrá
authors.forename: M C
authors.initials: MC
authors.lastname: Crespo Maraver
authors.forename: L M
authors.initials: LM
authors.lastname: Molinero
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D007802:Language; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000175:diagnosis*; D013030:Spain; D011795:Surveys and Questionnaires; D014177:Translations