The
Definition Of

Attention-deficit hyperactivity disorder or ADHD

A considerably more common childhood disorder is attention-deficit hyperactivity disorder or ADHD, a disorder marked by inattention, impulsiveness, a low tolerance for frustration, and generally a great deal of inappropriate activity. Although all children show such behavior some of the time, it is so common in children diagnosed with ADHD that it interferes with their everyday functioning.

 ADHD is surprisingly widespread, with estimates ranging between 3 and 5 percent of the school-age population – or some 3.5 million children under the age of 18 in the United States. Children diagnosed with the disorder are often exhausting to parents and teachers, and even their peers find them difficult to deal with.

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