title: Vision-specific quality of life and modes of refractive error correction.
abstract: OBJECTIVE
  Many studies currently use surveys to assess patients' reports of vision-specific quality of life to determine the impact of the disease or the most appropriate mode of treatment. One such instrument, the National Eye Institute Visual Function Questionnaire (NEI-VFQ), was developed to assess vision-related quality of life with respect to emotional well-being and social function as well as difficulty with tasks and symptoms. We administered the NEI-VFQ to 218 subjects free of eye disease to see if the survey was sensitive enough to detect differences in three modes of refractive error correction: spectacles, soft contact lenses, and rigid contact lenses.
  
  
  METHODS
  Surveys were administered to 117 rigid contact lens wearers, 51 spectacle wearers, and 50 soft contact lens wearers. Kruskal-Wallis one-way analysis of variance was conducted to determine significant differences in each of the subscales.
  
  
  RESULTS
  The Peripheral Vision subscale score (mean +/- SD) was 92.6 +/- 15.2 for the spectacle wearers, 100.0 +/- 0.0 for the soft contact lens wearers, and 98.3 +/- 7.1 for the rigid gas-permeable contact lens wearers; the spectacle wearers' Peripheral Vision score was significantly lower than the other two groups (Wilcoxon rank sum, p < 0.003 for both). The spectacle wearers (96.6 +/- 9.2) also had a significantly lower Dependency subscale score than the rigid contact lens group (99.7 +/- 1.5) (Wilcoxon rank sum, p = 0.001). There were no significant differences between the three groups detected in the mean of any of the other subscale scores. At least 50% of the subjects reported the maximum score for 6 of the 11 subscales. Given our sample size, we have 100% power to detect a difference of 10 points with a SD of 10 at the alpha = 0.05 level.
  
  
  CONCLUSIONS
  The NEI-VFQ is not appropriate for detecting significant differences in vision-related quality of life among spectacle, soft contact lens, and rigid gas-permeable contact lens wearers, primarily due to maximum ratings by many of the subjects.
authors.affiliation: The Ohio State University College of Optometry, Columbus 43210-1240, USA. walline.1@osu.edu
authors.forename: J J
authors.initials: JJ
authors.lastname: Walline
authors.forename: M D
authors.initials: MD
authors.lastname: Bailey
authors.forename: K
authors.initials: K
authors.lastname: Zadnik
mesh_terms: D000293:Adolescent; D000328:Adult; D003261:Contact Lenses; D003263:Contact Lenses, Hydrophilic; D005139:Eyeglasses; D005260:Female; D006305:Health Status Indicators; D006306:Health Surveys; D006801:Humans; D008297:Male; D011788:Quality of Life; D012030:Refractive Errors / Q000628:therapy*; D014785:Vision, Ocular / Q000502:physiology*