Every so often there is a story in the popular press raising concerns about either an increase in the rate of ADHD (implying excessive diagnosing of ADHD) and/or the over treatment of ADHD. If one delves into these stories more fully it appears that they are relying on the Centers for Disease Control* estimates of ADHD. The most recent data from the CDD, from 2011, put the rate of ADHD at 11%, and show a steady increase in the rate of ADHD (rising from 7.8% in 2003). However, these figures are based on parent reports, which Russel Barkley Ph.D. suggests make it quite likely that the prevalence of ADHD is being over-reported.** In recent comments on the prevalence of ADHD Barkley cites an article by Song and colleagues that finds that more rigorous studies of the rates of prevalence of ADHD show rates of as being in the 4-5% rate, which has been the accepted estimate for many years.
Russell Barkley also suggests that there are a number of “subthreshold cases of ADHD. He discusses a study by Biderman and colleagues that identified a subthreshold group of children. These children had multiple symptoms that are typically associated with ADHD, but did not evidence a sufficient number of symptoms (e.g., less than 6 symptoms) or reported a delayed age of onset for ADHD (after 7 years of age). As a result, these children did not meet criteria for a diagnosis of ADHD. However, Barkley noted that these children were found to have multiple problems relative to control group children (a normal problem free group). These children were identified as more often having other disorders (such as anxiety and depression), and significantly higher scores on the Child Behavior Checklist (which rates social and behavioral functioning). Barkley notes that these children appear far more like children with ADHD, than normal problem free children. He argues that treating these children is the humane and appropriate approach, and that worries about over-treatment minimize the real issues and challenges these children experience.
Taken together the data on prevalence and the argument for treating those who are experiencing real problems, suggests that concerns about the over-diagnosis and over-treatment of ADHD may be over-blown. This is not to suggest that there are not problems with over-diagnosis (this is clearly an issue, particularly for certain groups were diagnosis seeking for standardized testing may be occurring or simplistic solutions are sought for complex problems) do not exist. Rather, it is to suggest that there is no crisis involving the over-diagnosis of ADHD.
Song, M., et al., Addressing discrepancies betweebn ADHD prevalance and case identification estimates among U.S. children utilizing NSCH 2007-2012. Journal of Attention Disorders 2018.
Barkley R., The ADHD Report, Volume 26, Number 8, Dec. 2018, page. 10-11.
Biderman, J. et al. Further evidence of morbidity and dysfunction associated with subsyndromal ADHD. Journal of clinical Psychiatry, 2018 Aug 7;79(5). pii: 17m11870. doi: 10.4088/JCP.17m11870