Qurexa Logo
Qurexa

Trust. Care. Deliver.

Back to Blog & Insights
Lifestyle

2.1 million children studied: who gets an ADHD or autism diagnosis has quietly changed

Qurexa Editorial Team25 September 20266 min read 0 0
2.1 million children studied: who gets an ADHD or autism diagnosis has quietly changed

What happened

A large Danish study reported on 24 September 2026 has found that the kind of child receiving an ADHD or autism diagnosis has changed over the past decade. The researchers came from Aarhus University in Denmark and the Barcelona Institute for Global Health. They used Denmark's national health records, which is why the numbers are so big. They looked at more than 2.1 million children and adolescents. Within that group, they studied over 71,000 young people who were diagnosed with ADHD or autism between 2012 and 2022. They compared them with more than 713,000 undiagnosed peers who were similar in age and background. The finding was consistent. Children diagnosed more recently looked more like the general population than children diagnosed ten years earlier. That comparison covered several things: circumstances at birth, family income and education, whether there was a history of psychiatric conditions in the family, and how much the child had used healthcare services previously. On all of those, the gap between diagnosed children and everyone else narrowed over the decade. In other words, an ADHD or autism diagnosis in 2022 was being given to a broader, more ordinary cross-section of children than it was in 2012.

Why this matters

Diagnoses of ADHD and autism have risen sharply in many countries, including the UK. That rise gets talked about constantly, usually badly. One camp says it proves something is going wrong - that modern life, screens, or diet are causing a real increase. Another says it proves over-diagnosis, that ordinary childhood is being turned into a medical condition. This study offers a third explanation, and it is more boring and more likely than either: the threshold moved. Ten years ago, a child generally reached diagnosis only if their difficulties were severe, or if their family had the knowledge and resources to push for an assessment. Those children looked different from the average child in measurable ways - more healthcare use beforehand, more family psychiatric history, sometimes different socioeconomic circumstances. As awareness spread and services changed, children with less obvious difficulties, and children from families who would not previously have sought assessment, started being identified too. So the diagnosed group began to look more like everyone else. This matters practically for anyone planning services. If the profile of diagnosed children is shifting, then the support they need is shifting too. A service designed around the most severely affected children of 2012 may not fit the children arriving in 2026. It also matters for how we read research. The study authors made this point themselves.

What the evidence actually says

This is a strong study design, and it has real limits. Both are worth understanding. The strength is the data. Denmark keeps linked national registers covering essentially the whole population. That removes a problem most studies have, where the people who volunteer for research are not typical. Here, 2.1 million children means almost everyone. The finding is descriptive. It describes who was diagnosed and how that group's characteristics changed. It does not claim to explain why, and it does not measure whether any individual diagnosis was correct. That last point is important, because this study is easy to misuse. It does not say that ADHD and autism are over-diagnosed. It does not say recent diagnoses are wrong or less real. A child whose difficulties are less visible from the outside can still be struggling badly. What it does say is that rising diagnosis rates may partly reflect broader identification and changing diagnostic practice, rather than only an increase in the underlying conditions. The researchers also flagged a subtle consequence for science. Some recent studies have reported better outcomes among people diagnosed with ADHD or autism. That could mean support has improved. But it could partly reflect the fact that the group being studied has changed - a broader group, on average less severely affected, will naturally show better average outcomes without anything actually improving. That is a genuinely useful caution, and it applies to a lot of published research. One more limit: this is Denmark. Its health system, referral routes and cultural attitudes are not identical to the UK's. The direction of travel is likely similar. The specifics may not be.

Practical advice

If you are a parent in the middle of this, here is what is actually useful. If you are waiting for an assessment, this study is not a reason to doubt yourself. Waiting lists in the UK are long, and it is easy to start wondering whether you are making a fuss. Broader identification is not the same as wrongful identification. If your child is struggling, that is real regardless of where the threshold sits. If your child has been diagnosed recently, nothing here undermines it. The study describes population patterns, not individual cases. While you wait, support does not have to. Schools can put help in place without a diagnosis, through SEN support. You can ask to speak to the school's SENCO - the special educational needs co-ordinator - and ask what can be tried now. Many of the most effective adjustments are simple and do not require any formal label. Be cautious about paid private assessments advertised online with very short waiting times. Some are excellent. Some are not, and an assessment that the NHS or your local authority will not accept has cost you money for nothing. Check whether the provider is recognised locally before paying. And if you are an adult wondering about yourself, the same logic applies. Recognition of ADHD and autism in adults has widened considerably. Start with your GP. If you want reliable reading, the National Autistic Society and ADHD UK both publish clear, honest information.

What to know

Researchers from Aarhus University and the Barcelona Institute for Global Health studied more than 2.1 million Danish children, including over 71,000 diagnosed with ADHD or autism between 2012 and 2022. They found that children diagnosed more recently increasingly resemble the general population in their birth circumstances, family background, family psychiatric history and previous healthcare use. The diagnosed group has broadened. That suggests rising diagnosis rates partly reflect wider identification and changing practice, not only more of the underlying conditions. It also means research reporting improving outcomes needs reading carefully, because the group being studied has shifted. What it does not mean is that recent diagnoses are wrong, or that anyone should doubt a diagnosis they or their child has received. If you are waiting for an assessment, ask your child's school what support can start now. That is the thing you can change this week. Sources: ScienceDaily, 'ADHD and autism diagnoses have surged. A massive study may help explain why', 24 September 2026, https://www.sciencedaily.com/releases/2026/09/260924020353.htm; EurekAlert! / ISGlobal, 'Study suggests the profile of people diagnosed with ADHD and autism has changed over the past decade', 24 September 2026, https://www.eurekalert.org/news-releases/1143569; Medical Xpress, 'Study suggests profile of people diagnosed with ADHD and autism has changed over the past decade', September 2026, https://medicalxpress.com/news/2026-09-profile-people-adhd-autism-decade.html This article is for general information and does not replace advice from a doctor, pharmacist or other qualified healthcare professional.

#ADHD#autism#child health#research#diagnosis#families

Related articles