NEW HAVEN, Conn. (NBC) — A stunning new assessment of national numbers came out today: and it got the attention of a lot of us. It’s about attention deficit – ADHD – and the extraordinary number of cases now being diagnosed: one in five high school-aged boys in the US, fifteen percent of ALL school-aged boys , eleven percent of all kids in the nation – and these numbers show a 16 percent rise in cases since 2007. That’s leading to questions about whether ADHD is being over-diagnosed and whether the medicine to treat it is being overused.

14-year-old Kai Holme and his 12-year-old brother Casen spend a lot of time outdoors staying as active as possible.

The boys sometimes have a tough time sitting still; both were diagnosed with ADHD when they were younger.

Their mom, Karen, first noticed it when the boys had trouble completing simple homework assignments.

“It was such a struggle we only got 6 problems done in one hour and in-between that time he blurted out mommy I can’t think, I just can’t think,” said Karen.

According to data collected by the CDC and analyzed by the New York Times, the number of children diagnosed with ADHD is increasing.

The Times analysis showed an estimated 6.4 million children ages 4 through 17 have ADHD.

Those numbers reflect a 53 percent jump in the past decade.

Nearly two-thirds of those children get prescriptions with amphetamine type drugs to help treat the disorder. Sales of those drugs reached 9-billion dollars last year.

“I think this is of great concern. I think that there’s some over-diagnosis and over-treatment going on under the guise of other conditions,” said Dr. William Graf of Yale.

It is not just children diagnosed with ADHD – studies show that on college campuses and high schools across American, many students routinely take the drugs to enhance their performance on examination.

That raises many concerns.

“Just, how is this acting on the brain in the long-term of children?” asked Dr. Graf.

Experts said there is no question that some children like the Holmes have genuine problems that can be helped with the medications. But many worry there is too much diagnosis and too much medication.

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