According to the report, published in the National Center for Health Statistics Data Brief for August 2011, the increase may be influenced by racial, ethnic, and economic factors.
ADHD is one of the most common mental health disorders of childhood, but its frequency varies by race and ethnicity, the CDC says. Symptoms of ADHD include inattention, impulsive behavior, and hyperactivity.
Race, Ethnicity, and Income Factors in ADHD Diagnosis
The CDC, analyzing trends in children age 5 to 17, says that between 1998 and 2009: