(AP Photo)

(CNSNews.com) - More than 20 percent of the 14-year-old boys in the United States have been diagnosed at some point in their lives with attention-deficit/hyperactivity disorder (ADHD), according to a newly released study by the federal Centers for Disease Control and Prevention.

The study also said more than 20 percent of 11-year-old boys had been diagnosed with ADHD at some point in their lives.

The study indicated that American boys were 125 percent more likely than girls to be diagnosed with ADHD, and that boys were 127 percent more likely than girls to be medicated for it.

13.3 percent of American 11-year-old boys are being medicated for ADHD, said the study.

Overall, the percentage of children from 4 through 17 years of age who have been diagnosed with ADHD increased 42 percent from 2003 through 2011.

The study also found that children in public health programs (Medicaid and the State Children’s Health Insurance Program) were 53 percent more likely to be diagnosed with ADHD than children with private health insurance.

“The parent-reported prevalence of a history of an attention-deficit/hyperactivity disorder (ADHD) diagnosis by a health care provider among U.S. school-aged children increased from 7.8% in 2003 to 11% in 2011, an increase of 42% in less than a decade,” said the study published by the Journal of the American Academy of Child & Adolescent Psychiatry.

“This study is really based on the parent-reported survey data and it extends what we know about the increasing prevalence of health-care-provider diagnosed ADHD,” said Susanna Visser of the National Center on Birth Defects and Developmental Disabilities in a CDC podcast.

“It highlights the consistent increases in ADHD diagnoses since 2003,” said Visser, who is one of the authors of the study. “Now we also document that there’s been significant increases in the percentage of kids 4-17 years of age who are taking medication for ADHD since 2007.”

ADHD diagnoses, according to the study, are not distributed evenly among the nation’s children.

“Ever-diagnosed ADHD was more common among children with health care coverage than those without coverage, and among those with public coverage than with private coverage,” said the study.

“Nearly 1 in 5 high school boys and 1 in 11 high school girls had been diagnosed with ADHD,” said the study.

“Estimates of medicated ADHD increased in 2011, as compared to 2007, particularly among teen boys. In 2011, the highest medicated ADHD prevalence was among 11-year-old boys (13.3%).”

The study was based on the National Survey of Children’s Health, which has been conducted in three phases, including one in 2003, another in 2007, and a third in 2011. The survey interviewed a random sample of tens of thousands of parents (95,677 in the 2011-2012 phase), asking each parent interviewed about one child in their family. Among the questions asked was whether a doctor or other health provider had ever told the parent the child in question had ADHD, and whether this child is currently taking medication for ADHD.

In the 2003 survey, 7.8 percent of parents said their child had been diagnosed at some point with ADHD. In 2007, 9.5 percent said that, in 2011, 11.0 percent said that.

Children who did not have health-care coverage were least likely to have been diagnosed with ADHD, and children children on Medicaid and SCHIP were most likely. In the 2011 survey, 6.4 percent of children without health coverage were diagnosed, compared to 9.4 percent with private coverage, and 14.4 percent with Medicaid or SCHIP.

The 14.4 percent of children on Medicaid or SCHIP diagnosed with ADHD was 125 percent more than the 6.4 percent with no health coverage and 53 percent more than the 9.4 percent with private health coverage.

According to the 2011 survey, 15.1 percent of all American boys 4 to 17 years old have been diagnosed at some point with ADHD. That compares with 6.7 percent of girls in that age bracket. Thus, boys are 125 percent more likely than girls to be diagnosed with ADHD.

The 2011 survey also showed that 8.4 percent of American boys who are 4 to 17 years old are currently being medicated for ADHD, while only 3.7 percent of girls are being currently medicated. Thus, boys are 127 percent more likely than girls to be medicated for ADHD.

The study said: “Among boys, the 2003 prevalence of ever diagnosed ADHD … was less than 15%, regardless of age; in 2007, the estimates exceeded 15% for individuals 9 to 17 years of age, with the exception of those 12 years of age (13.6%); in 2011 the estimates exceeded 15% for those 10 to 17 years, and exceeded 20% for those 11 years and 14 years.”

“Nationally, the increases in parent-reported ADHD diagnosis and associated medication treatment occurred during a period in which the Food and Drug Administration (FDA) issued 3 Public Health Alerts and a series of communications regarding cardiac and psychiatric risks of ADHD medications,” said the report.

The CDC describes ADHD symptoms as follows: “A child with ADHD might: daydream a lot, forget or lose things a lot, squirm or fidget, talk too much, make careless mistakes or take unnecessary risks, have a hard time resisting temptation, have trouble taking turns, have difficulty getting along with others”

“We also have new information from the survey about the age of health-care-provider diagnosed ADHD and overall we estimate that children are diagnosed at an average age of 7, with about half of these children diagnosed by age 6,” said the CDC’s Visser in her podcast.