Setting the Record Straight on ADHD Prevalence

ADHD prevalence rates affected by diagnostic criteria and who reported the diagnosis

(RxWiki News) Controversy swirls around whether ADHD is over- or underdiagnosed — bringing into question the real rate of ADHD. New evidence sheds light on the factors that may affect reported rates of ADHD.

The authors of a new report reviewed published research to determine an estimate of the rate of attention deficit hyperactivity disorder (ADHD). They explained that variations in estimates may be due to which diagnostic criteria were used, who reported a child had ADHD and what region the child lived in.

"Media reports of high rates of diagnosis may cause suspicion regarding the diagnosis overall," wrote lead author Rae Thomas, PhD, of Bond University in Queensland, Australia, and colleagues. "[It] can lead to stigma for those diagnosed with the condition."

Thomas M. Seman, MD, a pediatrician in Boston, told dailyRx News that parents shouldn't always worry about every possible symptom of ADHD in their children because many kids appear hyperactive or unfocused from time to time.

"Instead, when the symptoms cause issues at school and at home then a parent needs to consider ADHD as a possible reason," Dr. Seman said. "Easy frustration, inconsistent performance at school and avoidance of doing homework can also be signs of this disorder."

Dr. Seman continued, "If the parent has any concerns they should talk to their child's teacher and primary care physician and see if an evaluation is necessary."

Dr. Thomas and team looked at 175 studies published on children aged 18 and younger with ADHD. They studied the factors that went into making an ADHD diagnosis. The team also looked at how those factors affected the determination of the frequency of ADHD.

Using the results of all the studies, Dr. Thomas and team estimated that 7.2 percent of all children had ADHD.

The Diagnostic and Statistical Manual of Mental Disorders (DSM) provides the guidelines doctors use to diagnose mental health disorders like ADHD. 

Dr. Thomas and team found that the rate of ADHD varied when different versions of the DSM were used to make the diagnosis.

The prevalence was 3 percent lower when the revised third edition of the DSM was used to make the diagnosis — compared to using the fourth edition of the DSM.

Studies using the criteria from the fourth edition of the DSM found the rates of ADHD were greater than 10 percent.

Location and who reported the ADHD diagnosis also factored into the rate.

Children who lived in the Middle East had a 4 percent higher rate of ADHD diagnoses than those who lived in North America.

When doctors reported cases of ADHD, research studies found an ADHD rate of 5.9 percent. When teachers reported numbers of children with ADHD symptoms, the rate rose to 13.3 percent.

“An accurate diagnosis is arguably the single most important thing a clinician can do for a patient," Dr. Thomas and team wrote. "Our estimates may help to better establish population-based benchmarks for clinicians to consider."

ADHD is a chronic condition with symptoms like trouble paying attention, impulsiveness and hyperactivity. It is most common in children but can sometimes continue into adulthood. Parents who think their children might have ADHD should talk to a doctor.

This study was published online March 2 in the journal Pediatrics.

Dr. Thomas and team disclosed no funding sources or conflicts of interest.

Review Date: 
February 27, 2015