"Our findings indicate a continuous increase in the prevalence of diagnosed ADHD among U.S. children and adolescents," coauthor Wei Bao said in a statement.
The analysts saw an upward trend across gender, race, family and geography, but all the increases were not uniform.
As for gender, their findings showed that 14 percent of boys were diagnosed with ADHD in 2016, compared to 9 percent in 1997. On the other hand, girls saw just a 3 percent hike, from 3.1 percent diagnosed in 1997 to 6.3 percent in 2016.
Across racial lines, African-American children had the biggest surge. More than 12 percent of African-American kids were diagnosed with ADHD in 2016, up from 4.7 percent in 1997. White children had the second biggest, from 7.2 percent in 1997 to 12 percent in 2016. Hispanic children diagnosed with ADHD jumped from 3.6 percent to 6.1 percent within the same time span.
The numbers varied by geography, too. The researchers said children in the Western region were less likely to be diagnosed with ADHD, compared to those in the Northeast, Midwest or South. Diagnoses in the Western region only saw a 2 percent boost from 5 percent in 1997 to 7 percent in 2016, while the other regions all exceeded 10 percent in 2016.
While the authors did not explore the cause of the uptick, they hypothesized that more awareness of ADHD and a diminished social stigma for ADHD could all be factors. They noted previous studies, which said environmental, prenatal and perinatal risk factors could also be components.
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