The Preschool Test is a valid index of visual acuity recorded in terms of a 30-foot denominator. It is intended for Pre-school children and has given reliable results from the age of two years and up. The Preschool / Allen Test is also useful for mas screening or for individual testing. No pretraining of younger children is necessary.
Comparison of the visual acuity of a child's two eyes is more important than absolute values obtained. Normal children between 2 and 3 years of age can usually identify the pictures at 12 to 15 feet. Children between 3 and 4 can usually identify them at 15 to 20 feet. Adults with excellent visual acuity can recognize them at distances greater than 30 feet in good light. A difference of 5 feet between a child's two eyes is probable cause for referral.
Washable durable plastic cards are printed front and back with seven different images.