With back-to-school on the horizon, one New Jersey doctor suggests taking your child for an eye exam as soon as possible.

About 24% of children who have refractive vision problems don't get them fixed, Dr. Joseph Calderone of Better Vision New Jersey in Cranford said. This can lead to plummeting grades, frequent headaches and even symptoms that appear similar to ADHD, such as lack of focus, he said

Calderone said parents can do a lot to prevent vision issues in their children, simply by observing and watching them.

If a child needs glasses, he or she will squint to see better. While many parents rely on vision screening tests at school, these tests can miss up to 60% of treatable vision problems, so Calerdone said parents should consider taking their childred to get eye exams before each school year begins.

Back in the day, sitting too close to a TV used to be a dead giveaway that a child had a vision problem, according to Calderone. But nowadays, all little kids have access to handheld devices, and little kids have little arms and hold these devices close by. Also, the proliferation of 55 inch screen televisions make it easier to see even with mediocre vision.

So Calderone said the rule of thumb for parents is this: "If you can see something in the distance, your child should also be able to see it. Not being able to see what you see is a strong indicator of vision difficulties."

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