The ADHD explosion: A new book explores factors that have fueled it

The authors of the new book--psychology professor Stephen P. Hinshaw and health economist Richard M. Scheffler, both of UC Berkeley, are hardly ADHD deniers: They acknowledge ADHD to be a disorder that can hobble the lives of those who have it, and they cite abundant evidence that the prescription stimulant medication used to tame ADHD's symptoms can bring about remarkable improvement in those with the disorder. Their research is underwritten by the Robert Wood Johnson Foundation, a respected public health philanthropy.

But the line that separates the merely scattered and energetic child from one who fits the disorder's full clinical criteria is not sharp. And Hinshaw and Scheffler argue that our shifting expectations of our kids' (and our own) economic and academic performance have tilted the balance in favor of diagnosing an underachieving child and of medicating him or her with the stimulant drugs used to blunt the disorder's symptoms.

Following is a Q&A with the book's authors, conducted and edited by Los Angeles Times staff writer Melissa Healy:

Q. You’ve described the diagnosis and medication of ADHD as “exploding” in the United States, and you’ve chronicled the increase in childhood ADHD diagnoses from 1 in 20 kids in the 1980s and '90s to 1 in 9 today—roughly 6.4 million kids between the ages of 4 and 18. Is ADHD at this point an overdiagnosed condition? Or are diagnoses just catching up to the true prevalence of this disorder in the U.S.?

Hinshaw: It looks pretty clear around the world that in any country with compulsory education, the prevalence of ADHD is remarkably similar—around 5% of schoolkids. That’s roughly how frequently you see ADHD diagnosed in Brazil, China, Europe and elsewhere.

But the ADHD diagnosis rate in the U.S. is quite high compared to that of other highly developed countries. If you believe the most current data from the Centers for Disease Control and Prevention, the latest figure is that 11% of all kids 4 to 17 have at some point gotten an ADHD diagnosis from a professional. And after first grade, it’s 20% of all boys and about 10% of all girls. If you believe those data, which appear to be accurate, we have gone too far. That’s higher than the diagnostic rate should be.

There are too many diagnoses made in children on the basis of maybe a 10- to 15-minute visit to a pediatrician’s office, where there’s no corroborating information from the child’s school, no ratings from his or her parents, no thorough history taken of the kid. And at the end of such a brief office visit, a prescription for stimulant medication is often written. Now, that’s a formula for overdiagnosis, since the symptoms of ADHD are also the symptoms of some learning disabilities, of depression, of having been mistreated, or of a chaotic classroom. ADHD too often can be a convenient label to describe problems that have other origins.

But the same very cursory process can lead to underdiagnosis of ADHD. The physician says, “Well, I didn’t see her tearing up the waiting room,” or, “his parents say he can play video games for six hours straight, so it can’t be ADHD.” In these instances, the physician doesn’t have a sense of the child in the classroom or at home or on the soccer field. And the result can be that the diagnosis is missed, leaving a child struggling. It’s problematic either way.

Professional groups—the American Academy of Pediatrics, the American Academy of Child and Adolescent Psychiatry, the American Psychiatric Assn.—have all published very clear guidelines as to what a thorough assessment for ADHD requires. But there’s no enforcement of those guidelines. And there’s usually no insurance reimbursement to physicians for making such a thorough assessment.

Scheffler: Over- and underdiagnosis comes in part from the clinical reality of how the ADHD diagnosis is made. There is no blood test, no brain scan, no X-ray you can point to and say, “There it is!” So it can be a matter of judgment from the parents, clinicians, even the children themselves. There’s some fuzziness around the edges of this diagnosis.

In the absence of clear physical basis for a diagnosis, our changing societal expectations and economic conditions can play a role in how willing people are to diagnose and medicate a child for ADHD. After all, this is a disorder whose hallmarks are impulsive, disruptive and inattentive behavior and academic underperformance. So, part of the explosion we have seen in ADHD diagnoses comes from escalating academic pressure that teachers and parents have placed on their children to perform better at school, to get into a better college, to get a good job.

Q. What do state policies on educational accountability have to do with ADHD?

Scheffler: There’s been a recent history of trying to get our schools to perform better. Fifteen or 20 years ago, the philosophy was to get class sizes down and to fund schools better: In efforts to improve education, the focus was on inputs. Then, with [the federal] No Child Left Behind [law]—and a wide range of state educational accountability measures that came before it—the focus of improving education shifted to output: better test scores, higher graduation rates, etc.

This enormous “push for performance” unleashed a whole new focus on testing, and on generating positive test results. The movement tied school and school district  budgets, teachers’ salaries, and principals’ promotions to these test scores.

But let’s look at the incentives this creates for diagnosing ADHD in children who might be bringing down their school’s average test scores, or who may be disruptive forces in their classrooms. First, of course, there’s this belief that diagnosing and medicating kids with ADHD will help them do better. But it goes beyond that: Once a child is diagnosed with ADHD, the school is also allowed to make accommodations in his or her testing, for instance, which can help him or her get better test scores. And sometimes, diagnosing a child with ADHD allowed the school to exempt that child’s scores from the measures by which the school and its administrators are evaluated and either rewarded or punished.

In some sense, we can see the societal pressure pushing everyone to diagnose. These state and eventually federal policies incentivized schools to do that. A fairly clever natural experiment  helped us to measure this effect. One by one in the 1990s, 30 states passed these kinds of accountability laws incentivizing test scores and achievement. Those states were mostly in the U.S. South. And sure enough, through the late 1990s and in the first years of the new century, those states saw dramatically increased rates of ADHD diagnoses.

Then in 2002, along came the No Child Left Behind law, which made these performance-based standards for education the law of the land. The day it takes effect in 2003, the law brings 20 states into this new push-for-performance scheme. And it’s targeting public schools, and especially public schools in low-income communities—schools that received a lot of funding for free and reduced-price lunch programs.

Hinshaw: Now, the law takes effect in 2003. And, as luck would have it, 2003 is when the CDC conducts  the first national survey that asks a representative sample of parents whether their child had ever been diagnosed with ADHD by a professional. And then, four years later, they ask the same question in another representative survey.