It's tricky to diagnose.
"There is still no test that tells us conclusively that a child has ADHD," says Dr. Pearson. This fuels skeptics' belief that children are misdiagnosed. But doctors rely on a comprehensive developmental history, detailed questionnaires, and rating scales that assess a child's behavior and level of impairment over the years. By talking to the child, parents, teachers--and, if necessary, grandparents, babysitters, and even coaches--doctors determine whether her symptoms are normal for a kid her age or whether they're causing serious problems at home or at school. They must also rule out other factors--such as anxiety, a learning disability, depression, or perhaps divorce or an ill family member--that might be triggering symptoms.