title: Psychometric performance of the NEI VFQ-25 in visually normal Latinos: the Los Angeles Latino Eye Study.
abstract: OBJECTIVE
  To characterize the psychometric performance of the National Eye Institute 25-item Visual Function Questionnaire (NEI VFQ-25) in visually normal Latinos (Mexican Americans).
  
  
  METHODS
  The Los Angeles Latino Eye Study (LALES) is a population-based study to assess the prevalence of eye disease and self-reported visual functioning in Latinos aged 40 or more years. Self-reported visual functioning was assessed by using English and Spanish versions of the NEI VFQ-25. Psychometric properties of the NEI VFQ-25, including internal consistency of the subscales and the individual items, were assessed through the Multi-trait Analysis Program-Revised (MAP-R) analysis. Adjusted mean and median subscale scores were compared between English and Spanish speakers to identify any systematic differences.
  
  
  RESULTS
  Of the 1917 participants from two census tracts, 1171 participants with no visual impairment were included in this analysis. The mean age of the participants was 52.3 years, 57% of the participants were female, and 67.5% of the participants were Spanish speaking. Median scores for Spanish-speaking participants were significantly lower than those of the English-speaking participants on four subscales: Ocular Pain, General Vision, Vision-Specific Mental Health, and General Health (P < 0.05). Internal consistency for three of eight measurable subscales for the study group was poor (Cronbach alpha < 0.6).
  
  
  CONCLUSIONS
  This study reveals psychometric inconsistencies in the NEI VFQ-25 when administered to visually normal Latinos. The difference in mean subscale scores between Spanish and English speakers must be integrated into the development of population norms of visual function. Further detailed psychometric evaluation is needed to determine the validity of this instrument in Latino populations.
authors.affiliation: Department of Pharmaceutical Economics and Policy, School of Pharmacy, Keck School of Medicine, University of Southern California, Los Angeles, California, USA.
authors.forename: Denise
authors.initials: D
authors.lastname: Globe
authors.forename: Rohit
authors.initials: R
authors.lastname: Varma
authors.forename: Stanley P
authors.initials: SP
authors.lastname: Azen
authors.forename: Sylvia
authors.initials: S
authors.lastname: Paz
authors.forename: Elaine
authors.initials: E
authors.lastname: Yu
authors.forename: Susan
authors.initials: S
authors.lastname: Preston-Martin
mesh_terms: D000203:Activities of Daily Living; D000328:Adult; D005260:Female; D006801:Humans; D007802:Language; D015141:Los Angeles / Q000453:epidemiology; D008297:Male; D017058:Mexican Americans; D008875:Middle Aged; D011594:Psychometrics / Q000592:standards*; D015203:Reproducibility of Results; D018434:Sickness Impact Profile; D011795:Surveys and Questionnaires; D014786:Vision Disorders / Q000208:ethnology / Q000503:physiopathology; D014785:Vision, Ocular / Q000502:physiology*