Related Experiment Video
Updated: Aug 10, 2026
The Measurement and Treatment of Suppression in Amblyopia
Published on: December 14, 2012
The amblyopia treatment study visual acuity testing protocol
J M Holmes1, R W Beck, M X Repka
1Mayo Clinic, Ophthalmology West 7, Rochester, MN 55905, USA. holmes.jonathan@mayo.edu
Objective:
To evaluate the reliability of a new visual acuity testing protocol for children using isolated surrounded HOTV optotypes.
Methods:
After initial pilot testing and modification, the protocol was evaluated using the Baylor-Video Acuity Tester (BVAT) to present isolated surrounded HOTV optotypes. At 6 sites, the protocol was evaluated for testability in 178 children aged 2 to 7 years and for reliability in a subset of 88 children. Twenty-eight percent of the 178 children were classified as having amblyopia.
Results:
Using the modified protocol, testability ranged from 24% in 2-year-olds to 96% in 5- to 7-year-olds. Test-retest reliability was high (r = 0.82), with 93% of retest scores within 0.1 logMAR unit of the initial test score. The 95% confidence interval for an acuity score was calculated to be the score +/-0.125 logMAR unit. For a change between 2 acuity scores, the 95% confidence interval was the difference +/-0.18 logMAR unit.
Conclusions:
The visual acuity protocol had a high level of testability in 3- to 7-year-olds and excellent test-retest reliability. The protocol has been incorporated into the multicenter Amblyopia Treatment Study and has wide potential application for standardizing visual acuity testing in children.
