No abstract

To evaluate the effectiveness of a lowvision rehabilitation program.Methods: A multicenter randomized clinical trial was conducted from November 2004 to November 2006 with a 4-month follow-up. A total of 126 patients were included, 98% of whom were white and male. The patients were referred from eye or low-vision clinics and blind rehabilitation centers with a visual acuity in the better-seeing eye worse than 20/100 and better than 20/500 and were eligible for Veterans Affairs (VA) services. Telephone interviews of patients were conducted in their homes before and after participation in an outpatient low-vision program at a VA medical care facility or a (waiting list) control group. The interviewer administering questionnaires by telephone was masked to patients' assignments. Interventions included low-vision examination, counseling, and prescription and provision of low-vision devices and 6 weekly sessions provided by a low-vision therapist to teach use of assistive devices and adaptive strategies to perform daily living tasks independently.Main Outcome Measure: Change in patients' visual reading ability estimated from participant responses to the Veterans Affairs Low-Vision Visual Functioning Questionnaire (LV VFQ-48) reading items completed at baseline compared with 4 months after enrollment for the treatment and control groups. The secondary outcomes were changes in other visual ability domains (mobility, visual information processing, visual motor skills) and overall vi-sual ability from baseline to 4 months estimated from VA LV VFQ-48 difficulty ratings for subsets of items.Results: The treatment group demonstrated significant improvement in all aspects of visual function compared with the control group. The difference in mean changes was 2.43 logits (95% confidence interval [CI], 2.07-2.77; P Ͻ.001; effect size, 2.51) for visual reading ability; 0.84 logit (95% CI, 0.58-1.10; P Ͻ .001; effect size, 1.14) for mobility; 1.38 logits (95% CI, 1.15-1.62; PϽ.001; effect size, 2.03) for visual information processing; 1.51 logits (95% CI, 1.22-1.80; P Ͻ .001; effect size, 1.82) for visual motor skills; and 1.63 logits (95% CI, 1.40-1.86; P Ͻ .001; effect size, 2.51) for overall visual function. Conclusion:The program effectively provided lowvision rehabilitation for patients with macular diseases.Applications to Clinical Practice: At least 10 hours of low-vision therapy, including a home visit and assigned homework to encourage practice, is justified for patients with moderate and severe vision loss from macular diseases. Because the waiting-list control patients demonstrated a decline in functional ability, low-vision services should be offered as early as possible.

Visual ability is a composite variable with two factors; one most heavily influences reading function and the other most heavily influences mobility function. Subsets of items within the AI and different VFQs all measure the same visual ability variable.