Wes Streeting, then health secretary, spoke confidently about mental-health overdiagnosis while the government was preparing welfare cuts.
Months later, he acknowledged that the issue was more complicated and commissioned an independent review. Its interim report found recorded ADHD prevalence below estimated population levels, alongside sharply rising referrals and waiting lists. It did not establish excessive diagnosis as the cause of that demand.
The political conclusion came first
On 16 March 2025, Streeting was asked whether some mental-health conditions were being overdiagnosed.
He said there was “definitely” an overdiagnosis and spoke about too many people being “written off”. His comments came two days before the government published its Pathways to Work Green Paper.
The Green Paper proposed tighter Personal Independence Payment rules. Claimants would have needed to score at least four points in one daily-living activity to qualify for the daily-living component. It also proposed cutting the Universal Credit health element for many new claimants from £97 to £50 a week.
Streeting’s comments landed inside a live argument about reducing disability-related spending. They were not merely observations about clinical practice.
Claims of overdiagnosis are useful during welfare reform. They move attention away from whether people receive enough healthcare and support. Instead, the public is encouraged to ask whether some of them deserve help at all.
A shortage of services can be recast as an excess of patients. People seeking assessment can be presented as people seeking an excuse.
Streeting did not specifically say that ADHD was overdiagnosed in that interview. His claim concerned mental-health conditions more broadly.
ADHD and autism were later included in the government’s independent review into rising diagnoses, demand for services and access to support.
By then, the frame was already in place: perhaps too many people were being labelled, and perhaps those labels were contributing to welfare dependency.
The evidence was less convenient
In December 2025, Streeting acknowledged that his earlier answer had failed to capture the complexity of the issue. He commissioned a review led by Professor Peter Fonagy, with Professor Sir Simon Wessely and Professor Gillian Baird serving as vice-chairs.
Commissioning the review was the right decision. The problem was that Streeting had already supplied the political conclusion before the evidence had been gathered.
The interim report did not rule out overdiagnosis in every clinic, age group or assessment route. It said that underdiagnosis, misdiagnosis and overdiagnosis could exist at the same time. It also made clear that it was not yet offering final conclusions or recommendations.
Its ADHD findings did not support a simple national story of excessive diagnosis.
Recorded ADHD prevalence in health systems was 1.19% in June 2025. That remained below the population estimates commonly used in clinical guidance. The report also found that people reporting a professional ADHD diagnosis almost all screened positive on the available adult ADHD measure, while only a minority of those who screened positive reported a diagnosis, treatment or self-identification.
That does not prove every assessment is correct. It does show that rising demand cannot simply be treated as evidence that clinicians are diagnosing too many people.
The report found that relatively stable estimates of underlying ADHD prevalence could exist alongside sharply rising diagnoses, referrals and service demand. Possible explanations included better recognition, changing help-seeking, institutional incentives and pressure within existing service pathways. The data could not yet show the contribution made by each factor.
That uncertainty should have produced caution from the start.
A waiting list is not a diagnosis
Open referrals for children and young people awaiting ADHD assessment in mental-health services rose from about 21,000 in April 2019 to around 270,000 in December 2025.
Those children and young people had not all received diagnoses. Many had not yet reached an assessment.
A waiting list measures demand and pressure on services. It does not show how many referrals will result in a diagnosis.
Yet political debate often merges referrals, diagnoses and benefit claims into one vague picture of a system handing out labels too easily.
The figures instead show an assessment system struggling to respond. The review described slow and fragmented pathways, weak data and support systems that rely heavily on diagnostic categories.
A formal diagnosis has also become a route to educational help, workplace adjustments, treatment and recognition. The interim report noted that when access to assistance depends on diagnosis, demand for assessment can rise faster than services can cope.
When support is locked behind a diagnosis, people will seek a diagnosis.
That does not mean their difficulties are invented. It means a clinical label has become the key to several different doors.
Politicians can then point to the queue for that key as evidence that too many people want one.
The more useful question is why practical help is so often withheld until someone has completed a slow medical process.
Streeting gave the right a useful premise
Streeting did not create the political attack on diagnosis and disability support. He gave it authority.
In August 2025, Policy Exchange published Out of Control, a report about psychiatric and neurodevelopmental conditions among children and young people. It argued that incentives across health, education and welfare systems were driving overdiagnosis and encouraging families to seek diagnoses to unlock support. Former Conservative health secretary Jeremy Hunt wrote its foreword.
The Conservatives went further in June 2026. They promised that a future Conservative government would reassess what they called “mild” PIP claims involving anxiety, depression and ADHD. Their announcement paired those conditions with claims that people who could work were refusing to do so while receiving benefits.
This language treats ADHD less as a condition whose effects vary between people and more as a suspicious category of welfare spending.
Streeting may not have intended that use. Intent is not the main issue. Ministers are responsible for the political effects of claims made with the authority of government.
Once a Labour health secretary had described overdiagnosis as a definite problem, right-wing organisations could push the claim further while presenting it as political common ground.
They could say that even Labour accepted the premise.
The argument could then move from examining diagnostic standards to questioning the legitimacy of disabled people.
The correction came too late
The interim report leaves important questions unanswered.
It does not establish that every diagnostic service operates well. It does not settle whether thresholds have shifted in particular settings. It does not prove that overdiagnosis never occurs.
It does, however, undermine the idea that excessive ADHD diagnosis is an adequate explanation for rising demand.
The evidence points to low recorded prevalence, huge assessment queues, inconsistent access, incomplete data and institutions that often demand diagnostic proof before offering practical help.
Streeting was entitled to ask whether overdiagnosis was occurring. He should not have spoken as though the answer was already known, particularly while his government was preparing to reduce disability support.
A health secretary’s words do not remain inside a television interview. They become headlines, assumptions and political ammunition. They shape how patients, claimants and families are viewed long before a review reports.
Streeting asked for the evidence only after making the claim. In the meantime, that claim helped legitimise a right-wing attack on diagnosis and disability support.
Whatever the final report concludes, some of the political damage has already been done.
A later report can correct the record. It cannot erase the headlines, suspicion and policy arguments that the original claim helped create.