According to the American Optometric Association, the average school screening looks for less than 4% of what a comprehensive eye exam can determine and fails to detect 75% of children with vision problems. These screenings cannot accurately identify many of the visual problems children may have. There are a number of issues, such as near vision problems, eye tracking problems, problems with focusing, and difficulties with eyes working together when reading from a book or computer screen, each of which has an effect on learning. A vision screening determines whether a student is able to see the appropriate sized target 20 feet away. However, less than 25% of what the student does academically in a classroom setting takes place at that distance. The academic demand is likely to increase as time goes on, but the screening requirements remain constant. In light of all these factors, a school vision screening alone is simply not sufficient.

Do school vision screenings have any value?

These screenings are seen by some parents as a formality, and they do not bother getting their kids properly examined if they fail the screening. In fact statistics show that up to 67 percent of children who fail vision screenings do not receive an eye examination or vision care from an optometrist.
While the school screening is limited in value, it is still a good first indication if your child has any issues with distance vision. While Dr. McBryar hopes that the standards for school screenings evolve with our understanding of vision; she still believes that parents should have their children do school screenings and bring those results in when they schedule a developmental eye exam.

Why are school vision screenings not enough?

Performing a developmental comprehensive eye exam is always recommended when a child is about to start formal schooling. In addition, when you have a student who appears to be struggling academically, but you don't know for sure why they're not able to achieve their cognitive potential, they should be scheduled for a developmental eye exam. By assuming that all potential vision problems have been ruled out by the vision screening, it may result in a student getting pushed towards 504 or IEP plans, and a diagnosis of ADD or ADHD when in fact it may be caused in part to the underlying vision problem.