title: Validity, reliability, and repeatability of the useful field of view test in persons with normal vision and patients with glaucoma.
abstract: OBJECTIVE
  To determine the validity, test-retest reliability and repeatability of the UFOV test in healthy controls and glaucoma patients.
  
  
  METHODS
  Three substudies with the UFOV test were conducted: (1) validity was evaluated in 77 older controls (mean age 64 [SD, 7] years) and 53 glaucoma patients (mean age 69 [SD, 8] years); (2) test-retest reliability was evaluated in 13 young controls (mean age 28 [SD, 4] years), 21 older controls (mean age 66 [SD, 9] years), and 22 glaucoma patients (mean age 68 [SD, 8] years) who performed the test twice within approximately two weeks; (3) repeatability was evaluated in 17 young controls (mean age 33 [SD, 8] years) who performed the test five times on the same day.
  
  
  RESULTS
  In the validity substudy, mean total processing time was significantly less for older controls (358.3 ms [SD, 226.8 ms]), than glaucoma patients (580.2 ms [SD, 324.5 ms]), with moderate correlations (rho ≥ 0.40) between total processing time and age, and visual field impairment. In the reliability substudy, mean total processing time was significantly less on retest (P ≤ 0.02), with glaucoma patients showing the largest mean test-retest difference (144.7 ms [SD, 168.9 ms]) compared with young (31.5 ms [SD, 43.7 ms]) and older controls (56.2 ms [SD, 74.8 ms]). The 95% limits of agreement were significantly wider for glaucoma patients (-186.3 and +475.7 ms) compared with young (-54.1 and +117.1 ms) and older controls (-90.5 and +202.9 ms), (P < 0.01). In the repeatability substudy, performance remained constant after the second of five tests (differences in mean total processing time <6 ms).
  
  
  CONCLUSIONS
  Measurement properties of the UFOV test are important for assessing functional performance, in particular, fitness to drive. Our results indicate moderate variability, greater for glaucoma patients than healthy controls, and a learning effect. Two consecutive tests are suggested to establish reliable baseline measures.
authors.affiliation: Department of Ophthalmology and Visual Sciences, Dalhousie University, Halifax, Canada. sharon.bentley@deakin.edu.au
authors.forename: Sharon A
authors.initials: SA
authors.lastname: Bentley
authors.forename: Raymond P
authors.initials: RP
authors.lastname: LeBlanc
authors.forename: Marcelo T
authors.initials: MT
authors.lastname: Nicolela
authors.forename: Balwantray C
authors.initials: BC
authors.lastname: Chauhan
mesh_terms: D000328:Adult; D000368:Aged; D001334:Automobile Driving; D005260:Female; D005901:Glaucoma / Q000503:physiopathology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D012016:Reference Values; D015203:Reproducibility of Results; D014786:Vision Disorders / Q000503:physiopathology*; D015348:Vision, Binocular / Q000502:physiology; D014792:Visual Acuity / Q000502:physiology; D058609:Visual Field Tests; D014794:Visual Fields / Q000502:physiology*; D019987:Persons with Visual Disabilities