An official government-commissioned review in England has delivered a verdict that will reshape how neurodevelopmental conditions are understood, diagnosed and funded: there is, it says, a genuine risk that ADHD and autism are moving from an era of under-diagnosis into one of over-diagnosis or mis-diagnosis. The findings, published on 9 October 2026 in a 607-page report, are likely to feed into everything from NHS services and school support to benefits policy — and they have already reopened one of the most sensitive debates in British public life.
What the review actually found
The review was chaired by Professor Peter Fonagy, the British psychoanalyst and clinical psychologist, and commissioned in December 2025 by the then health secretary Wes Streeting, who had voiced concern about over-diagnosis among young people. What emerged is more nuanced than either side of the debate may have hoped.
The central finding is statistical. Over the past 25 years, diagnoses of ADHD and autism have risen so sharply that for some younger age groups the numbers now appear to outstrip the expected level in the population. More than 4 per cent of children aged six to 17 are now diagnosed with autism — well above the 1 to 2 per cent that epidemiological studies suggest is the true prevalence. The review warned of a risk of blurring the line between diagnosable ADHD and autism and what should be considered normal human variation in brain function, cognition and behaviour. In the reviewers' words, not every difficulty requires a medical response.
But the report stops short of declaring that mass over-diagnosis is happening right now. Because some of the key figures date back nearly a decade, the reviewers said it was not possible to be absolutely certain, or to conclude that over-diagnosis was currently occurring at scale. And on the broader question of young people's mental health, Fonagy pushed back hard against the political framing that had launched the review. Speaking to BBC Radio 4's Today programme, he said Streeting had been, with respect, completely wrong to suggest there was widespread over-diagnosis of mental health disorders. Distress among young people, the review concludes, is real and rising — driven by anxiety and depression as much as by neurodevelopmental labels.
Why diagnoses have surged
The review identifies a web of causes rather than a single culprit. Economic uncertainty and the pressures of social media are named as forces driving an increase in mental health problems among young people. Poorer sleep, weaker feelings of connection and belonging, and uncertainty about the future all feature in the report's account of why more young people are seeking answers — and why diagnosis has increasingly become the narrow doorway through which people try to reach support for complex needs.
There is also a cultural dimension. Greater awareness has undoubtedly helped people who were previously overlooked — particularly girls and women, and adults whose ADHD or autism went undetected in childhood. But awareness, amplified by social media algorithms that reward short, relatable symptom checklists, can also lower the threshold at which ordinary struggles get medicalised. The review's framing is careful: diagnosis remains essential and must be protected, but it should no longer be the only route through which help can be reached.
The labour-market stakes are stark. About a third of young people aged 16 to 24 who are outside education, employment or training say their mental health or autism plays a part, and young people diagnosed with ADHD before turning 17 are four times as likely as their peers to end up in that group. Whether those figures reflect the consequences of the conditions themselves, the failure of support systems, or the distorting effect of the labels, is precisely what the policy response must now disentangle.
The private assessment boom — and the call for tougher rules
Perhaps the review's most concrete recommendation concerns the fast-growing private market for assessments. With NHS waiting lists for ADHD diagnosis in England now exceeding 700,000 people, families are being pushed into a poorly regulated private sector where, the reviewers said, there are concerns about quality and consistency.
The report calls for private firms offering assessments for the NHS to be brought under tougher regulation, and goes further on marketing: it wants a ban on advertising diagnostic assessments directly to the public. The government has said it will bring these providers under Care Quality Commission regulation, and Health Secretary Yvette Cooper is to write to the Advertising Standards Authority to ensure companies give people accurate information when marketing diagnostic appointments. The authors of the review would go further still and stop assessments being marketed to the public altogether.
