Considered a heritable brain disorder, one in nine U.S. children—or 6.4 million youth—currently have a diagnosis of ADHD. In recent years, parents and experts have questioned whether the growing prevalence of ADHD has to do with hasty medical evaluations, a flood of advertising for ADHD drugs, and increased pressure on teachers to cultivate high-performing students. Now Brown and other researchers are drawing attention to a compelling possibility: Inattentive, hyperactive, and impulsive behavior may in fact mirror the effects of adversity, and many pediatricians, psychiatrists, and psychologists don’t know how—or don’t have the time—to tell the difference.

Though ADHD has been aggressively studied, few researchers have explored the overlap between its symptoms and the effects of chronic stress or experiencing trauma like maltreatment, abuse and violence. To test her hypothesis beyond Baltimore, Brown analyzed the results of a national survey about the health and well-being of more than 65,000 children.

Brown’s findings, which she presented in May at an annual meeting of the Pediatric Academic Societies, revealed that children diagnosed with ADHD also experienced markedly higher levels of poverty, divorce, violence, and family substance abuse. Those who endured four or more adverse childhood events were three times more likely to use ADHD medication.

Interpreting these results is tricky. All of the children may have been correctly diagnosed with ADHD, though that is unlikely. Some researchers argue that the difficulty of parenting a child with behavioral issues might lead to economic hardship, divorce, and even physical abuse. This is particularly true for parents who themselves have ADHD, similar impulsive behavior or their own history of childhood maltreatment. There is also no convincing evidence that trauma or chronic stress lead to the development of ADHD.

For Brown, who is now a pediatrician at Montefiore Medical Center in the Bronx, the data are cautionary. It’s not evident how trauma influences ADHD diagnosis and management, but it’s clear that some misbehaving children might be experiencing harm that no stimulant can fix. These children may also legitimately have ADHD, but unless prior or ongoing emotional damage is treated, it may be difficult to see dramatic improvement in the child’s behavior.

“We need to think more carefully about screening for trauma and designing a more trauma-informed treatment plan,” Brown says.

Dr. Kate Szymanski came to the same conclusion a few years ago. An associate professor at Adelphi University’s Derner Institute and an expert in trauma, Szymanski analyzed data from a children’s psychiatric hospital in New York. A majority of the 63 patients in her sample had been physically abused and lived in foster homes. On average, they reported three traumas in their short lives. Yet, only eight percent of the children had received a diagnosis of post-traumatic stress disorder while a third had ADHD.