Attention-deficit/hyperactivity disorder: are we helping or harming?

Summary box

• Clinical context—The prevalence of attention-deficit/hyperactivity disorder (ADHD) has increased substantially in the past decade, with most children diagnosed with ADHD described as having mild or moderate ADHD. Medication prescription rates have also increased twofold for children and fourfold for adolescents and adults

• Diagnostic change—Definitions of ADHD have been broadened in successive editions of DSM

• Rationale for change—Concern that ADHD is underdiagnosed in some children and adults

• Leap of faith—Identifying and treating more people with ADHD will improve their quality of life

• Impact on prevalence—The prevalence of parent reported diagnosis of ADHD in the US rose from 6.9% in 1997 to 9.5% in 2007. In the Netherlands it doubled over a similar period and other countries have also seen similar rises

• Evidence of overdiagnosis—Severity of ADHD criteria is subjective. Prevalence varies markedly within and between countries and there is evidence that inappropriate developmental comparisons, sex, and heuristics contribute to inappropriate diagnoses

• Harms from overdiagnosis—Medication costs of inappropriately diagnosed ADHD are estimated to be between $320m (£200m; €230m) and $500m in the US and some children have adverse drug reactions. While a diagnosis may help children and families it also carries stigma; children labelled as having ADHD are perceived as lazier and less clever by peers, and teachers and parents have low academic expectations of them potentially creating a self fulfilling prophecy

• Limitations—Longitudinal data on the prognosis of ADHD and effects of treatments are limited

• Conclusions—Reducing the threshold for diagnosing ADHD devalues the diagnosis in those with serious problems. A conservative stepped diagnostic approach could reduce the risk of overdiagnosis