ADHD is diagnosed by. Clinical criteria of 6/9 or > significant symptoms of Inattention +/- Hyperactivity /Impulsivity that caused harmful dysfunction at home & school for 6 mos. Or > by age 10, even if ADHD-Primarily Inattentive Type was not diagnosed in childhood. There are no biological markers; neuropsychological deficits found in people with ADHD are also found in people with other Neurodevelopmental Disorders.
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