Although most Americans who have vision problems are 65 years or older, even preschoolers may not see as well as they should. Young children may be nearsighted, which means distant objects look blurred.
Another cause of vision problems in young children is amblyopia, which affects 2 to 4% of preschoolers. Amblyopia, also called lazy eye, is poor vision in one eye that is otherwise physically normal. Treatment includes finding the condition early, and using a patch or eye drops to give the stronger eye a rest and to strengthen the weaker eye.
Just one of every seven preschoolers receives an eye exam, and fewer than one of four receives some type of vision screening. Because finding amblyopia early is important for treating it effectively, the U.S. Preventive Services Task Force recommends vision screening for amblyopia and its risk factors for all children ages 3 to 5 years.
Source: Centers for Disease Control and Prevention, CDC.gov