Development of the 25-item National Eye Institute Visual Function Questionnaire

Objective: To develop and lest the psychometric properties of a 25-item ver sion of the National Eye institute Visual Function Questionnaire (NEI VFQ-2 5). Design: Prospective observational cohort study of persons with 1 of 5 chron ic eye diseases or low vision who were scheduled for nonurgent visits in op hthalmology practices and a reference sample of persons without eye disease . S Setting: Eleven university-based ophthalmology practices and the NEI Clinic al Center. Patients: Eligible participants had to have 1 of the following eye conditio ns: age-related cataracts, age-related macular degeneration, diabetic retin opathy, primary open-angle glaucoma, cytomegalovirus retinitis, or low visi on from any cause. Seven of the 12 sites also enrolled persons in a referen ce sample. Reference sample participants had no evidence of underlying eye disease but were scheduled for either screening eye examinations or correct ion of refractive error. All eligible persons had to be 21 years or older, English speaking, and cognitively able to give informed consent and partici pate in a health status interview. Measurements and Main Results: To provide the data needed to create the NEI VFQ-25, all subjects completed an interview that included the 51-item NEI VFQ. Estimates of internal consistency indicate that the subscales of the N EI VFQ-25 are reliable. The validity of the NEI VFQ-25 is supported by high correlations between the short- and long-form versions of the measure, obs erved between- group differences in scores for persons with different eye d iseases of varying, severity, and the moderate-to-high correlations between the NEI VFQ-25 subscales that have the most to do with central vision and measured visual acuity. Conclusions: The reliability and validity of the NEI VFQ-25 are comparable to those of the 51-item NEI VFQ field test version of the sun ey. This shor ter version will be more feasible in settings such as clinical trials where interview length is a critical consideration. In addition, preliminary ana lyses indicate that the psychometric properties of the NEI VFQ-25 are robus t for the eye conditions studied; this suggests that the measure will provi de reproducible and valid data when used across multiple conditions of vary ing severity.