The DSM IV definition of Attention-Deficit Hyperactivity Disorder (ADHD) is:
A. Either (1) six (or more) of the following symptoms of inattention have persisted for at least 6
months to a degree that is maladaptive and inconsistent with developmental level; or (2) six (or more) of the following symptoms of hyperactivity-impulsivity have persisted for at least 6 months to a degree that is maladaptive and inconsistent with developmental level:
B. Some hyperactive-impulsive or inattentive symptoms that caused impairment were present before age 7 years.
C. Some impairment from the symptoms is present in two or more settings (e.g. at school [or work] and at home).
D. There must be clear evidence of clinically significant impairment in social, academic, or occupational functioning.
E. The symptoms do not occur exclusively during the course of a Pervasive Developmental Disorder, Schizophrenia, or other Psychotic Disorder and are not better accounted for by another mental disorder (e.g. Mood Disorder, Anxiety Disorder, Dissociative Disorder, or a Personality Disorder) (Shin, 1998, pp.316-7).
Inattention can be observed in a person that displays these symptoms: often fails to give close attention to details or makes careless mistakes in schoolwork, work, or other activities; often has difficulty sustaining attention in tasks or play activities; often does not seem to listen when spoken to directly; often does not follow through on instructions and fails to finish schoolwork, chores, or duties in the workplace ( not due to oppositional behavior or failure to understand instructions); often has difficulty organizing tasks and activities; often avoids, dislikes, or is reluctant to engage in tasks that require sustained mental effort ( such as schoolwork or homework); often loses things necessary for tasks or activities (e.g. toys, school assignments, pencils, books, or tools); is often easily distracted by extraneous sti...