Figure 2:

Effect sizes comparing VSQOL in each VFL severity category to those without VFL

VSQOL = Vision-Specific Quality of Life; AFEDS = African American Eye Disease Study; VFL = Visual Field Loss; CTT = Classical Test Theory; IRT = Item Response Theory; ANCOVA = Analysis of Covariance; ES = Effect Sizes; NEI-VFQ-25 = National Eye Institute Visual Function; SF-12 = 12-Item Short-Form Health Survey

ES below 0.20 are negligible and not shown. ES from 0.20 to less than 0.50 are considered small, 0.50 to less than 0.80 are medium, and 0.80 or more are large.

ES were calculated from ANCOVA models as the difference in adjusted mean QOL scores for each VFL severity category and the no VFL category, divided by the standard deviation of QOL score in the no VFL group.

ES are shown for the NEI-VFQ-25 CTT composite, the IRT task and well-being composites, all 11 CTT subscales, and the general health item; CTT subscales are grouped by task or well-being and ordered by descending ES in the bilateral moderate/severe comparison. The SF-12 component scores are also shown.

VFL severity was stratified into five categories: no VFL (mean deviation [MD] > 2 decibels [dB] in both eyes), unilateral mild VFL (−6 dB <MD< −2 dB in the worse eye); bilateral mild VFL ( 6 dB < MD < 2 dB in both eyes; unilateral moderate-to-severe VFL (MD<−6 dB in one eye, MD > 2 dB in the other eye; or 6 dB < MD < 2 dB in one eye, MD < 6 dB in the other eye), and bilateral moderate-to-severe VFL (MD < 6 dB in both eyes).

*NEI-VFQ-25 item response theory and classical test theory composite scores are marked for emphasis.

^||Scores could be generated for only 4,574 of the participants who reported that they were currently driving or had driven in the past.