ADHD diagnoses have risen much faster than ADHD traits.

ADHD symptom and diagnosis trends in two Swedish datasets from 2004 to 2022

The animation first compares parent-rated ADHD traits and registered diagnoses among Swedish nine-year-olds from 2004 to 2014. It then reports that diagnoses continued to rise after 2014 and shows separate national estimates for 2022: about 6 in 100 girls and 11 in 100 boys aged 10 to 17. The later estimates use a different age group and source. An illustrative distribution stays fixed while a diagnostic boundary moves left, increasing the highlighted group. More diagnoses do not necessarily mean more ADHD symptoms.

Across recent decades, ADHD traits among Swedish children changed only a little.

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What the evidence shows

In 19,271 Swedish nine-year-old twins assessed from 2004 to 2014, registered ADHD diagnoses increased more than fivefold. Parent-rated ADHD traits at the diagnostic-level extreme showed no clear increase, although average and subthreshold trait scores rose slightly (Rydell et al., 2018).

Among Swedish 18-year-old twins assessed from 2011 to 2019, ADHD traits were stable among boys and rose slightly among girls. The increase was much smaller than the rise in diagnoses (Arvidsson et al., 2025).

Official Swedish estimates for children aged 10–17 continued upward. Among boys, diagnosed ADHD rose from 7.1% in 2015 to 10.5% in 2022; among girls, it rose from 2.9% to 6% (Socialstyrelsen, 2021; Socialstyrelsen, 2023).

The later symptom and diagnosis results come from different age groups and sources. They support the same broad pattern, but they are not one continuous series (Arvidsson et al., 2025; Rydell et al., 2018; Socialstyrelsen, 2023).

These are population trends. They do not explain why any individual child was or was not diagnosed, or how much better recognition, changing practice, changing demands, or overdiagnosis contributed (Kazda et al., 2021; Rydell et al., 2018).

References

  • Arvidsson, O., Brikell, I., Larsson, H., Lichtenstein, P., Kuja-Halkola, R., Johnson, M., Gillberg, C., & Lundström, S. (2025). ASD and ADHD symptoms in 18-year-olds—A population-based study of twins born 1993 to 2001. Psychiatry Research, 351, 116613. https://doi.org/10.1016/j.psychres.2025.116613
  • Kazda, L., Bell, K., Thomas, R., McGeechan, K., Sims, R., & Barratt, A. (2021). Overdiagnosis of attention-deficit/hyperactivity disorder in children and adolescents: A systematic scoping review. JAMA Network Open, 4(4), Article e215335. https://doi.org/10.1001/jamanetworkopen.2021.5335
  • Rydell, M., Lundström, S., Gillberg, C., Lichtenstein, P., & Larsson, H. (2018). Has the attention deficit hyperactivity disorder phenotype become more common in children between 2004 and 2014? Trends over 10 years from a Swedish general population sample. Journal of Child Psychology and Psychiatry, 59(8), 863–871. https://doi.org/10.1111/jcpp.12882
  • Socialstyrelsen. (2023). Diagnostik och läkemedelsbehandling vid adhd: Förekomst, trend och könsskillnader [Diagnosis and pharmacological treatment for ADHD: Prevalence, trends, and sex differences] (Publication No. 2023-11-8862). https://www.socialstyrelsen.se/contentassets/7cf0e4662040470a8d4db0710b751f83/2023-11-8862.pdf