The writing is on the chalkboard. Over the next few years, America can count on a major expansion of early childhood education. We embrace this trend, but as health policy researchers, we want to raise a major caveat: Unless we’re careful, today’s preschool bandwagon could lead straight to an epidemic of 4- and 5-year-olds wrongfully being told that they have attention deficit hyperactivity disorder.

Introducing millions of 3- to 5-year-olds to classrooms and preacademic demands means that many more distracted kids will undoubtedly catch the attention of their teachers. Sure, many children this age are already in preschool, but making the movement universal and embedding transitional-K programs in public schools is bound to increase the pressure. We’re all for high standards, but danger lurks.

The American Academy of Pediatrics now endorses the idea that the diagnosis of A.D.H.D. can and should begin at age 4, before problems accumulate. In fact, Adderall and other stimulants are approved for treatment of attentional issues in children as young as 3.

Early intervention for children with A.D.H.D. could provide great relief. Children who go untreated have major difficulties in school and with their peers, and they have higher-than-normal rates of accidents and physical injuries.

The problem is that millions of American children have been labeled with A.D.H.D. when they don’t truly have it. Our research has revealed a worrisome parallel between our nation’s increasing push for academic achievement and increased school accountability — and skyrocketing A.D.H.D. diagnoses, particularly for the nation’s poorest children.

For example, we found that in public schools, A.D.H.D. diagnoses of kids within 200 percent of the federal poverty level jumped 59 percent after accountability legislation passed, compared with under 10 percent for middle- and high-income children. There was no such trend in private schools, which are not subject to legislation like this.

By age 17, nearly one in five American boys and one in 10 girls has been told that they have A.D.H.D. That comes to 6.4 million children and adolescents — a 40 percent increase from a decade ago and more than double the rate 25 years ago. Nearly 70 percent of these kids are prescribed stimulant medications.

Families and physicians must take special care in medicating very young children. Today’s push for performance sets us on a troubling trajectory. A surge in diagnoses would mean more prescriptions despite guidance from professional organizations, including the American Academy of Pediatrics, which recommend that behavioral therapy rather than medication be used as first-line treatment for children under 6.

Too many kids are identified and treated after an initial pediatric visit of 20 minutes or even less. Accurate diagnosis requires reports of impairment from home and school, and a thorough history of the child and family must be taken, to rule out abuse or unrelated disorders.

Yes, this would be more time consuming and costly in the short term. But just like investing in preschool, spending more today on careful diagnosis and treatment of A.D.H.D. will lead to lifetimes of savings. As the early childhood education movement builds, let’s make sure we proceed with caution. We should fundamentally rethink how we diagnose and treat A.D.H.D., especially for our youngest citizens.

Stephen P. Hinshaw, a professor of psychology, and Richard M. Scheffler, a professor of health economics, both at the University of California, Berkeley, are the authors of “The ADHD Explosion: Myths, Medication, Money, and Today’s Push for Performance.”

[This article was originally posted on New York Times.]