How is ADHD diagnosed?
Children mature at different rates and have different personalities, temperaments and energy levels. Most children get distracted, act impulsively and struggle to concentrate at one time or another. Sometimes, these normal factors may be mistaken for ADHD.

ADHD symptoms usually appear early in life, often between the ages of 3 and 6, and because symptoms vary from person to person, the disorder can be hard to diagnose. Parents may first notice that their child loses interest in things sooner than other children, or seems constantly out of control. Often, teachers notice the symptoms first, when a child with ADHD has trouble following rules, or frequently "spaces out" in the classroom or on the playground.

No single test can diagnose a child with ADHD. Instead, a licensed health professional needs to gather information about the child, and their behavior and environment. A family may want to first talk with the child's pediatrician. Some pediatricians can assess the child themselves, but many will refer the family to a mental-health specialist with experience in childhood mental disorders such as ADHD. The pediatrician or mental-health specialist will first try to rule out other possibilities for the symptoms.

Between them, the referring pediatrician and specialist will determine if a child:

Is experiencing undetected seizures that could be associated with other medical conditions
Has a middle ear infection that's causing hearing problems
Has any undetected hearing or vision problems
Has any medical problems that affect thinking and behavior
Has any learning disabilities
Has anxiety or depression, or other psychiatric problems that might cause ADHD-like symptoms
Has been affected by a significant and sudden change, such as the death of a family member, a divorce, or parent's job loss.