The number of children diagnosed as having ADHD is rising rapidly, according to a study of more than 840,000 California children.
While the research findings echo those of nationwide studies, the new study is stronger than some other studies, says researcher Darios Getahun, MD, PhD, a scientist at Kaiser Permanente Southern California, a large health plan.
"We relied on the clinical diagnosis of ADHD [by doctors] and medication prescriptions rather than teacher or parent report," he says.
From 2001 to 2010, the rate of new cases of doctor-diagnosed ADHD rose from 2.5% to 3.1%, an increase of 24%.
"It's an increase that warrants attention," he says. Growing awareness of the condition is one reason for the rise, he speculates.
The study is published online in JAMA Pediatrics.
ADHD is one of the most common childhood neurobehavioral disorders, according to the CDC. Children with ADHD have trouble paying attention or act impulsively, or both.
While the American Psychiatric Association estimates that 3% to 7% of school-aged children have ADHD, other studies have found higher rates.
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