title: Danish version of Visual Function Questionnaire-25 and its use in age-related macular degeneration.
abstract: BACKGROUND
  Assessment of visual function can be a complex task and objective means of measurement of visual function do not always correlate with patients' self-perceived visual abilities. The purpose of this study was to translate the visual function questionnaire (VFQ)-25 into Danish with particular focus on its use in patients with late age-related macular degeneration (AMD).
  
  
  METHODS
  The translation was done in accordance with standard internationally adopted methods. This includes forward translation, back translation, examination of translation quality, and adjudication by bilingual speakers. We presented the questionnaire to 120 consecutive patients with exudative AMD referred to our department and to 25 healthy individuals. We tested the reliability of the Danish version by measuring test-retest reliability, estimated the internal consistency of the questionnaire (Cronbach's α-value) and analysed the discriminatory power (validity) of the questionnaire by comparing scores of patients with scores from control individuals without known eye disease.
  
  
  RESULTS
  The translated questionnaire produced high test-retest correlations (range 0.8-0.9), had a relatively high-level of internal consistency (range 0.4-0.9) and a high discriminatory power.
  
  
  CONCLUSIONS
  The Danish version of VFQ-25 produces acceptable values of validity and reliability in patients with AMD.
authors.affiliation: Department of Ophthalmology, Roskilde Hospital, Denmark.
authors.forename: Mette Sejer
authors.initials: MS
authors.lastname: Sørensen
authors.forename: Susanne
authors.initials: S
authors.lastname: Andersen
authors.forename: Gitte Osterby
authors.initials: GO
authors.lastname: Henningsen
authors.forename: Charlotte Thornby
authors.initials: CT
authors.lastname: Larsen
authors.forename: Torben Lykke
authors.initials: TL
authors.lastname: Sørensen
mesh_terms: D000367:Age Factors; D000368:Aged; D000369:Aged, 80 and over; D003718:Denmark; D018450:Disease Progression; D005260:Female; D006305:Health Status Indicators; D006306:Health Surveys; D006801:Humans; D008268:Macular Degeneration / Q000175:diagnosis* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D015203:Reproducibility of Results; D013223:Statistics as Topic; D011795:Surveys and Questionnaires; D014787:Vision Tests