Visual acuity testing should be conducted separately for each eye because unilateral amblyopia is masked by the better-seeing eye when amblyopic children are tested binocularly.
Screening personnel need to monitor occlusion carefully because children with reduced vision in one eye often attempt to use their better eye by peeking.
Preferred methods of occlusion are to use adhesive eye patches or 2-inch wide hypoallergenic surgical tape (e.g., Micropore or Blenderm). An acceptable method is the use of specially constructed occluder glasses (e.g., Good-lite® opaque occluder glasses).
Holding a tissue, hand, paper cup, or an occluder paddle over a child’s eye is not acceptable because children can easily circumvent these types of occlusion.