A New Study Provides Insight Into Why So Many Children Are Misdiagnosed With ADHD

Children with August birthdays are more likely to get diagnosed with ADHD, researchers say.

Child holds up colorful ADHD sign.
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Children with August birthdays are more likely to get diagnosed with ADHD, researchers say.

The number of children diagnosed with Attention Deficit Hyperactivity Disorder, or ADHD, has continued to surge in recent years. Now researchers are trying to find out why. A new study provided by the New England Journal of Medicine is looking at elementary school cut-off dates as a probable cause leading to misdiagnosis of the disorder. The study found that kindergarten students who had only just turned 5-years-old before starting school in August were more likely to be diagnosed with ADHD than their older classmates, according to Today.

Although it may seem that a few months age difference wouldn’t make that much difference in a child’s behavior, the study proves otherwise. Researchers found that children with August birthdays were far more likely to be diagnosed and medicated for ADHD than those born in any other month.

During the study, researchers looked at statistics involving 407,846 children born between the years of 2007 and 2009. They then checked to see whether or not the child was being treated for ADHD and if so what their birth month was. Most elementary school cut-off dates for kindergarten require the child to have already turned 5-years-old prior to September 1 in order to enroll in the class. Otherwise the child would be expected to wait to enroll until the following year, making them among the older students in the class. As for the children who did make the cut-off date, but only by a few weeks or less, they had the highest chance of being treated for ADHD than any of their other classmates.

Because the stages of development progress quickly for this age group, even just a few months can really make a difference in terms of a child’s maturity level. David Anderson, senior director of the ADHD and Behavior Disorders Center and director of Programs at the Child Mind Institute, spoke about the connection between age and maturity in children.

“Some of the inattentive or distracting behaviors of ADHD could be aligned with typical behaviors of younger children. What the study is telling us is more of a verification,” he said. In other words, what could be mistaken as signs of ADHD, is often likely just a child acting normally for their age and maturity level.

How can families cut down on the misdiagnoses of ADHD in children who likely don’t require medication? They have to take in consideration a child’s developmental level before assuming that their behavior is automatically caused by the disorder, according to the study.