Responsiveness of the Revised Low Vision Independence Measure (LVIM-R).

Abstract

The Low Vision Independence Measure (LVIM) was designed to measure the effectiveness of occupational therapy to improve visual ability in low vision rehabilitation. To validate the Revised LVIM (LVIM-R) as an outcome measure by determining its sensitivity to visual ability changes after occupational therapy. In this observational study, LVIM-R scores were collected before and after customary low vision intervention. Home health agency or outpatient facility. Forty-four participants with a mean age of 80.2 yr (standard deviation = 11.2) and an average length of visual impairment of 6.2 yr. Twenty-three participants (52.3%) were treated in an outpatient setting, and 21 (47.7%) were treated in the home. The majority of participants were non-Hispanic White (92.8%) and had macular degeneration (54.5%). Customary low vision intervention by occupational therapists. LVIM-R scores were collected before and after intervention, and participants' pre- and posttest scores were anchored into Rasch-calibrated item parameters. Paired t tests demonstrated significant increases in person measures with large effect sizes for both constructs of the LVIM-R, the visual field or scotoma (t[43] = 6.46, p < .0001; Cohen's d = 0.92) and visual acuity (t[43] = 9.08, p < .0001; Cohen's d = 1.14) constructs. The LVIM-R is sensitive to changes in visual ability in clients who have good rehabilitation potential and can be used to examine the effectiveness of occupational therapy for low vision. The LVIM-R is useful for measuring occupational therapy outcomes in low vision rehabilitation in the home or in outpatient settings.