Reliability and validity of the National Eye Institute Visual Function Questionnaire-25 in patients with age-related macular degeneration.
OBJECTIVE
To evaluate the psychometric characteristics of the National Eye Institute Visual Function Questionnaire-25 (NEI VFQ-25) in patients with age-related macular degeneration (AMD) who participated in two clinical trials.


METHODS
A secondary analysis of data from two randomized clinical trials was performed. NEI VFQ-25 data were collected from 1134 of 1146 patients with subfoveal choroidal neovascularization due to AMD with minimally classic or occult with no classic types and predominantly classic type. The NEI VFQ-25 was administered at baseline and months 1, 2, 3, 6, 9, and 12, and the SF-36 Health survey was administered at baseline and months 6 and 12. Visual acuity assessments were completed monthly throughout the studies. Internal consistency reliability and construct validity were examined.


RESULTS
The average age was 77 years (SD = 7.5; range, 52-96) with 59% women. At baseline, internal consistency reliability was 0.96 for the NEI VFQ-25 total score and ranged from 0.62 (ocular pain) to 0.91 (near activities) for the subscales. NEI VFQ-25 total and subscale scores correlated significantly with SF-36 scores (P < 0.05), and total, near activities, distance activities, and dependency scores correlated significantly with best corrected visual acuity (BCVA) in the better (P < 0.0001) and worse seeing eye (P < 0.0001). Mean NEI VFQ-25 total and subscale scores, except for ocular pain and general health, varied by BCVA group (P < 0.001), with higher impairment scores seen in the lower visual acuity groups.


CONCLUSIONS
The NEI VFQ-25 demonstrated good reliability and construct validity as a measure of vision-related functioning outcomes in patients with AMD.
Revicki
Dennis A
DA
Center for Health Outcomes Research, United BioSource Corporation, Bethesda, Maryland 20814, USA. dennis.revicki@unitedbiosource.com
Rentz
Anne M
AM
Harnam
Neesha
N
Thomas
Vince S
VS
Lanzetta
Paolo
P
D000368:Aged; D000369:Aged, 80 and over; D017326:Clinical Trials, Phase III as Topic; D015350:Contrast Sensitivity / Q000502:physiology*; D004185:Disability Evaluation; D005260:Female; D006302:Health Services Research; D006306:Health Surveys; D006801:Humans; D008268:Macular Degeneration / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D054554:National Eye Institute (U.S.); D011594:Psychometrics; D015203:Reproducibility of Results; D018434:Sickness Impact Profile; D011795:Surveys and Questionnaires; D014481:United States; D014792:Visual Acuity / Q000502:physiology*