Data came from the parents of almost 23,000 children aged 6-17. The parents were asked, in telephone interviews conducted from 2004 to 2006, if a doctor or other health professional had ever diagnosed their child with ADHD or attention deficit disorder (ADD). The CDC didn't check the children's medical records to confirm the parents' reports.
ADHD diagnoses were twice as common among boys as girls. ADHD was also more common among adolescents and teens than younger kids, among whites or African-American children than among Hispanic children, and among kids covered by Medicaid than uninsured or privately insured kids.
The CDC also reports a 3% average annual increase in childhood ADHD diagnoses from 1997 to 2006, and that children with ADHD diagnoses were more likely than other kids to have other chronic health conditions.
The CDC's latest ADHD statistics only capture diagnosed cases of ADHD. The true number of children with ADHD may be much higher, researchers from Cincinnati Children's Hospital and the University of Cincinnati College of Medicine reported in September 2007.