Our response to BBC Autism Story: Function, not category

The BBC's 22 August 2026 feature “A split in the spectrum?” set out a long-running argument about whether the autism spectrum has become too broad. In Australia that argument is not hypothetical: it is already embedded in Commonwealth policy, in the NDIS reform legislation passed this month, and in the public statements of the Minister Butler.

Position in brief

1. We agree with the grievance. People with autism who also have intellectual disability and high support needs are under-researched and under-supported. That is real and it is not answered by anything in this paper.

2. We do not accept the proposed remedy. Narrowing the diagnostic category changes who counts. It does not change what is funded. Every version of this argument produces contested eligibility, not increased support.

3. Australia has already answered the question the international debate is still asking, and answered it in a defensible direction: the National Disability Insurance Scheme Amendment (Securing the NDIS for Future Generations) Act 2026 removes diagnosis lists as the means of entry and replaces them with standardised assessment of functional capacity from 1 January 2028. Assessing what a person can do is better than assessing what a person is called. We support that direction, to a point.

4. We are raising one specific and serious risk with how it is built. A functional-capacity assessment that records a level rather than a range will systematically misread people with AuDHD, whose defining feature is that capacity varies. It will do so by the same mechanism that made their diagnoses late in the first place — a mechanism with published Australian evidence behind it.

5. The people this will affect cannot currently be counted. Australia has no published national estimate of how many people have both autism and ADHD. The data exists in the ABS microdata and has never been published. A reform that turns on assessing this population is being designed without knowing its size.

The article, and the argument inside it

On 22 August 2026 BBC News published "A split in the spectrum? The ongoing battle to define autism", by health correspondent Catherine Burns. It is the clearest public account yet of a disagreement that has run in autism research for years, and it is the immediate occasion for this article.

The article's starting point is scale. In England, autism diagnoses recorded on GP records have risen from just over 700,000 three years ago to around 1.1 million. The National Autistic Society's position is that this reflects the correction of significant historical underdiagnosis, particularly among women and older people. Others in the article read the same increase differently.

Four positions are set out, and it is worth separating them because they are frequently collapsed into one.

• That the spectrum has collapsed under its own breadth. Professor Dame Uta Frith, one of the field's founding researchers, argues that people included in the diagnosis now have needs too different to share a category, and that some adults have been misdiagnosed. Her scepticism is directed at a "late-diagnosed group, mainly females", whom she suggests may instead have anxiety, depression or OCD. She also dismisses the research literature on masking. She proposes a "pruned" spectrum, and is explicit that she does not want anyone's diagnosis removed retrospectively.

• That subtypes are the middle path. Professor Sir Simon Baron-Cohen agrees the term is too broad but proposes adding subgroups rather than narrowing the category — including subtypes for co-occurring conditions such as ADHD — and argues that autistic people should choose the labels.

• That the premise is wrong and the consequences are serious. The National Autistic Society describes the misdiagnosis argument as misinformation, notes that anyone diagnosed has been assessed against strict criteria, and warns that re-labelling people risks removing their support. Researchers including Dr Monique Botha and Dr Rachel Moseley reject the framing that late-diagnosed autistic people have an easier or lesser experience, and defend the quality of masking research.

• That the lived reality of very high support needs is being lost. Families of autistic adults with intellectual disability who need constant care describe an experience they cannot recognise in the same category as someone living independently. This is the part of the article we take most seriously, and we return to it in section 3.

The finding at the centre of it

The article reports research from the University of Cambridge finding that people diagnosed from late childhood onwards show an underlying genetic profile with more in common with ADHD and depression than with autism diagnosed in early childhood. In the article this is offered as possible support for the misdiagnosis argument. The study's lead researcher, Dr Varun Warrier, does not read it that way — he describes autism broadening out genetically.

There is a third reading, and the article does not offer it

A profile that sits between autism and ADHD is a reasonable description of AuDHD.

AuDHD appears in the article once — in a list of four labels one woman has been given since being diagnosed in her thirties, none of which she can make sense of. That is roughly its status in the entire debate, and it is why we are publishing this paper rather than leaving the argument to others.

The rest of this article sets out what follows from that reading: why people with AuDHD are identified late, what Australia is already doing about diagnosis-based eligibility, and where we think the Australian reform is at risk of repeating the same error at national scale.

2. Why this is already an Australian argument

The BBC's article describes a British dispute about a British system. Australian readers may assume it is someone else's argument. It is not.

• In August 2025 the Minister for Health, Disability and Ageing told the National Press Club that "[t]ens and tens of thousands of young children with mild to moderate developmental delay or autism are on a scheme set up for permanent disability," and that "one out of every ten 6-year-olds are in the NDIS, including 16 per cent of 6-year-old boys."

• The Grattan Institute's Saving the NDIS (June 2025) attributed a 32 per cent increase in reported child autism prevalence to the introduction of the NDIS itself, and almost half of new child diagnoses since 2013.

• Australian research reported in 2026 put the autism rate among children aged 5–14 at 4.3 per cent, up from 3.2 per cent in 2018.

• The OECD published a cross-country review in March 2026 attributing rising diagnoses to increased detection rather than increased prevalence, and noting an international shift toward basing entitlement on individual need rather than diagnosis.

• At 30 June 2026, 350,651 NDIS participants had autism recorded as their primary disability — almost 45 per cent of all 782,013 active participants.

So the question is live here, it is being asked by people with the authority to act on it, and it has already produced legislation. That is why we are publishing a position rather than a commentary.

3. Where we agree

People with autism who also have intellectual disability and high support needs are under-served, under-researched and frequently spoken over — including by advocacy organisations whose members look nothing like them.

We are a workplace body. Our mandate covers people with AuDHD across working life, and it does not entitle us to speak for families whose experience is not ours. We say plainly that their under-representation is a legitimate grievance, that it long predates this argument, and that it deserves an answer of its own.

Nothing in the rest of this paper is a reason to keep ignoring it.

4. Where we disagree

The remedy does not follow from the problem.

Narrowing a diagnostic category does not move a single dollar, therapy hour or support worker toward people with high support needs. It removes people from one group. It does not fund another. If the concern is that support is spread too thin, the argument is about the size of the pot, not the size of the population.

We are not aware of a case in which contesting who counts as disabled has produced more support for anyone. What it reliably produces is contested eligibility, longer waits, and people withdrawing from a process they no longer trust.

We would apply the same test to any subtype proposal. We are not opposed to greater diagnostic precision, and we would contribute to that work. We are opposed to precision that arrives without funding attached, because in disability and employment systems a new category has one dependable use: sorting people into who qualifies and who does not.

5. The cohort that is missing from the data

Australia's authoritative source is the ABS Survey of Disability, Ageing and Carers. Its 2022 results, published in Autism in Australia, 2022, contain a pattern that should end the over-diagnosis argument in its current form.

Summarised by the ABS: 3.1 per cent of people under 25 reported autism, against 0.3 per cent of people aged 25 and over.

There are two available readings of a forty-fold gap between children aged 10–14 and adults aged 40 and over.

The first is that autism genuinely became forty times more common in one generation. Nobody argues this.

The second is that Australians now in middle age were never identified, because the diagnostic criteria, the clinical awareness and the services that would have identified them did not exist when they were children. The 0.1 per cent is not a measure of how many older Australians are autistic. It is a measure of how many were ever looked at.

Two further figures from the same survey point the same way. Between 2018 and 2022 the number of Australian women and girls reporting autism rose 95.5 per cent, from 46,500 to 90,900. Over the same period the number of men and boys rose 24.2 per cent. Female growth ran at roughly four times the male rate — which is what catching up looks like, not what inflation looks like.

The pattern is corroborated outside the disability data. The AIHW's national record of ADHD medication shows the number of people dispensed ADHD medication rising from 2 per 1,000 population in 2004–05 to 22 per 1,000 in 2023–24. Within that, female rates overtook male rates in the 18–24 and 25–44 age groups for the first time in 2022–23, and across all adult age groups by 2023–24. Adult women are not developing ADHD. They are being identified.

A note on the evidence: autism in the SDAC is self-reported, not clinically verified. We flag this rather than leave it to be found. It cuts both ways — self-report may include people without a formal diagnosis, and it certainly excludes people who have never been assessed at all, which in the 40-and-over cohort is the larger effect.

6. Why people with AuDHD are identified late

The cohort whose diagnoses are questioned most sharply — adults, disproportionately women, identified after years of being treated for anxiety, depression or burnout — includes a substantial number of people with AuDHD. This is the intersection the Council exists to represent and it is almost entirely absent from the argument.

Co-occurrence is not marginal. A 2021 meta-analysis of 63 studies found a pooled current ADHD prevalence of 38.5 per cent among autistic people (95% CI 34.0–43.2). A 2020 meta-analysis of 22 publications covering 61,985 children and adolescents with ADHD found 21 per cent met the threshold for autism.

The mechanism is documented, and the evidence is Australian. Knott and colleagues (Monash University, published in the Australian & New Zealand Journal of Psychiatry in 2024) examined age at diagnosis and diagnostic delay across 677 Australians, including 213 with both diagnoses. They found:

• Delay to ADHD diagnosis: 4.22 years for the ADHD + autism group, against 3.49 years for ADHD alone.

• Delay to autism diagnosis: 4.27 years for the ADHD + autism group, against 3.15 years for autism alone.

• Delay to autism diagnosis for females with ADHD + autism: 5.30 years.

Their conclusion: having ADHD and autism together, and being female, were each associated with longer delays to diagnosis.

This matters more than it first appears. It shows that co-occurrence is not simply two conditions arriving together — it is itself an independent driver of diagnostic delay. Having both makes you harder to identify than having either.

That is what interaction effects look like in practice:

• Traits pull against each other. Structure-seeking against novelty-seeking. Rigidity against impulsivity. Withdrawal against over-commitment. Present in the same person, often in the same week.

• Presentation is therefore inconsistent across contexts and across days — and inconsistency is precisely what assessment processes have historically read as evidence that a person is not really autistic.

• Support needs are variable rather than fixed. Variable is not the same as low. Someone who manages on Tuesday and cannot function on Thursday is recorded as someone who manages.

• The result is a sequence of partial explanations — anxiety, depression, burnout, personality disorder — each of which describes something real and none of which describes the underlying pattern.

Late diagnosis, on this evidence, measures how long the system took. Treating it as evidence of over-diagnosis inverts cause and effect.

7. Australia has already answered the question the debate is still asking

The National Disability Insurance Scheme Amendment (Securing the NDIS for Future Generations) Act 2026 passed the Senate on 19 August 2026. Among the reforms the Commonwealth has published, two matter here. The Government will:

"Remove diagnosis lists as the means of entry to the NDIS."

"Introduce standardised, evidence-based assessments of a person's functional capacity to determine access to the NDIS."

These changes apply to prospective participants from 1 January 2028, with existing participants reassessed over a transition period. A Technical Advisory Group is to advise government on the threshold and the assessments for substantially reduced functional capacity.

We support this direction, and we want to be unambiguous about why.

The international argument is about what to call people. Australia's reform is about what people can do. The second question is the better one. It cannot be won by lobbying over labels, it does not require anyone to be removed from a category to make room for someone else, and it is the same test that Commonwealth anti-discrimination law has applied for thirty years.

It also makes the "prune the spectrum" argument largely obsolete here. If access turns on assessed function rather than diagnostic membership, then the size of the diagnostic category stops being the thing worth fighting about. Importing that fight into Australia now would be arguing about a gate that is being removed.

8. The risk we are raising

Supporting the direction is not the same as being relaxed about the instrument.

A functional-capacity assessment that records a level rather than a range will systematically misread people with AuDHD.

The defining feature of this population is not that capacity is low. It is that capacity is inconsistent — across settings, across days, and under cumulative load. A point-in-time assessment of a person whose capacity fluctuates records whichever day they were assessed on. If the assessment is a scheduled appointment that the person has prepared for, masked through, and spent days recovering from, it records the best available version of them and calls it their capacity.

This is not a speculative concern. It is the identical mechanism, documented by Knott and colleagues, that produced diagnostic delays of over four years in this cohort — inconsistency read as absence. Building it into a standardised national instrument would reproduce, at scale and with statutory force, the error that a peer-reviewed Australian study has already measured.

The stakes are not small. Public reporting of the reform package has put the expected effect at around 240,000 existing participants exiting the scheme by 2031, with a further 110,000 not entering. We do not treat those numbers as settled, and the Government has not published a breakdown by disability type. But an instrument applied at that scale must be right about variability, and a fluctuating-capacity population is the group most exposed to getting it wrong.

What we are asking for is narrow and buildable: that the assessment measure capacity over time and under load, not at a moment; that variability be recorded as a finding rather than resolved into an average; and that the Technical Advisory Group include people with AuDHD, whose specific presentation is the hardest case any such instrument will have to handle.

9. The workplace: adjustments already work on impact

Whatever happens to diagnostic categories, Australian workplace obligations do not depend on them, and should not be made to.

The Disability Discrimination Act 1992 (Cth) defines disability in entirely functional terms. Section 4 refers to loss of bodily or mental functions, to a disorder that results in a person learning differently, and to a disorder that affects thought processes, perception, emotions or judgment. No named diagnosis, diagnostic manual or subtype appears anywhere in the definition. The Act extends to disability that previously existed, may exist in future, or is merely imputed. In assessing unjustifiable hardship, section 11(1)(b) directs attention to "the effect of the disability" — not its classification.

Australian government guidance follows the same logic. JobAccess advises that a good adjustment is "tailored to the individual" and altered to meet "the changing needs of the individual," and that "[t]he simplest thing an employer can do is ask, rather than assume." Comcare directs employers to how a condition "affects their ability to undertake their work."

That framework already handles everything a subtype system claims to solve, and it handles variability better, because it is prospective and reviewable rather than fixed at a point of assessment.

The practical consequence for employers is that a redefinition of autism does not change their obligations. The practical risk is the opposite one: if subtypes are introduced and become visible to employers, they will be used as a sorting mechanism — a shorthand for how much accommodation a person is entitled to expect — which is precisely what the DDA's individualised test was designed to prevent.

The context is a labour market already failing this population. In 2022, autistic Australians of working age had a labour force participation rate of 50.2 per cent and an unemployment rate of 18.2 per cent, against 3.1 per cent for people without disability. There is no equivalent published figure for people with ADHD, because no national dataset reports one.

10. What we are asking for

1. Build variability into the functional-capacity assessment. The instrument commencing 1 January 2028 should assess capacity over time and under load rather than at a point, and should record fluctuation as a finding in its own right. An assessment that cannot distinguish "consistently limited" from "unpredictably limited" is not measuring functional capacity; it is sampling it.

2. Put people with AuDHD on the Technical Advisory Group. This population is the hardest case the instrument will face. Designing for it produces a better instrument for everyone; designing without it guarantees a known failure mode.

3. Publish the co-occurrence data that already exists. The ABS records all long-term conditions per person, and co-occurring autism and ADHD is identifiable in SDAC microdata. We could locate no published national estimate. The ABS has produced a standalone Autism in Australia publication for 2015, 2018 and 2022; there is no ADHD equivalent and no national ADHD prevalence estimate. A reform that turns on assessing this population should not be designed without knowing its size.

4. Close the adult assessment gap. The Medicare items for complex neurodevelopmental disorder assessment (135, 137, 139 and 289) are capped at patients aged under 25. Adults aged 25 and over have no autism-specific MBS assessment item. In 2023 a Senate committee heard that waiting times for an initial ADHD appointment were "typically between six and 18 months," and heard evidence from the ADHD Foundation that some professionals were charging up to $5,000 for assessments. It is not coherent to question the validity of adult diagnoses while adult diagnosis remains privately funded, unevenly available and, for many people, unaffordable.

5. Fund the gap directly rather than redrawing the boundary. People with autism and intellectual disability need research investment and support. Neither is created by removing anyone else from a category.

6. Keep workplace adjustments on the DDA's impact test. No subtype, tier or category should become a gateway to reasonable adjustments at work. The existing functional test is better law and better practice, and it already accommodates the variability that a category cannot.

11. About this article

This article is a statement of the Council's policy position. It is general information and analysis. It is not legal advice, medical advice, or advice about any individual's eligibility for the NDIS or any other program.

Figures are drawn from published Australian sources current at 26 August 2026 and are listed in full below. Where a figure could not be verified against a primary source, it is not used.

The AuDHD Council of Australia is the national peak body for people with co-occurring autism and ADHD, focused on working life. We are lived-experience-led and member-governed. Our mission is to improve employment access, retention, and career sustainability for people with AuDHD by influencing workforce policy and employer practice.

We hold no employment services contracts, deliver no NDIS services, and receive no program funding from the reforms discussed in this paper.

The point we would leave you with

A diagnosis arriving at 40 instead of 4 is a measure of how long the system took to see someone. It is not evidence that there was nothing to see.

Australia is about to replace diagnosis with a measurement of function. That is the right move. Whether it works depends entirely on whether the measurement can see a capacity that changes — and the people it will most easily miss are the ones it took the longest to find.

12. References

The article

0. Burns, C. A split in the spectrum? The ongoing battle to define autism, BBC News InDepth, 22 August 2026. https://www.bbc.com/news/articles/cdew81wd2y8o

Australian data

1. Australian Bureau of Statistics, Autism in Australia, 2022, released 11 October 2024. https://www.abs.gov.au/articles/autism-australia-2022

2. Australian Bureau of Statistics, Disability, Ageing and Carers, Australia: Summary of Findings, 2022, released 4 July 2024. https://www.abs.gov.au/statistics/health/disability/disability-ageing-and-carers-australia-summary-findings/latest-release

3. Australian Bureau of Statistics, Microdata and TableBuilder: Disability, Ageing and Carers, Australia. https://www.abs.gov.au/statistics/microdata-tablebuilder/available-microdata-tablebuilder/disability-ageing-and-carers-australia

4. Australian Institute of Health and Welfare, ADHD medications dispensed over time, last updated 20 May 2025. https://www.aihw.gov.au/mental-health/topic-areas/mental-health-prescriptions/adhd-medications-dispensed-overtime

5. National Disability Insurance Agency, Participant counts by diagnosis, data to 30 June 2026. https://dataresearch.ndis.gov.au/

6. National Disability Insurance Agency, Quarterly Report to Disability Ministers, Q4 2025–26. https://www.ndis.gov.au/publications/quarterly-reports

Policy and legislation

7. Disability Discrimination Act 1992 (Cth), ss 4, 5(2), 6(2), 11, 21A. https://www.legislation.gov.au/C2004A04426/latest/text

8. National Disability Insurance Scheme Amendment (Securing the NDIS for Future Generations) Act 2026; passed the Senate 19 August 2026. https://www.aph.gov.au/Parliamentary_Business/Bills_Legislation/Bills_Search_Results/Result?bId=r7487

9. Department of Health, Disability and Ageing, Securing the NDIS for future generations, April 2026. https://www.health.gov.au/sites/default/files/2026-04/securing-the-ndis-for-future-generations_0.pdf

10. The Hon Mark Butler MP, National Press Club Address: Securing the Future of the NDIS, 20 August 2025. https://www.markbutler.net.au/news/speeches/national-press-club-address-securing-the-future-of-the-ndis

11. Senate Community Affairs References Committee, Assessment and support services for people with ADHD, tabled 6 November 2023, ch. 3. https://www.aph.gov.au/Parliamentary_Business/Committees/Senate/Community_Affairs/ADHD

12. Medicare Benefits Schedule, Complex Neurodevelopmental Disorders and Eligible Disabilities — 1 March 2023 changes, items 135, 137, 139, 289. https://www.mbsonline.gov.au/

13. JobAccess, What is a workplace adjustment? https://www.jobaccess.gov.au/news/what-workplace-adjustment

14. Comcare, Providing reasonable adjustments. https://www.comcare.gov.au/claims/employer-information/providing-reasonable-adjustments

Research

15. Knott, R., Mellahn, O.J., Tiego, J., Kallady, K., Brown, L.E., Coghill, D., Williams, K., Bellgrove, M.A. & Johnson, B.P. (2024). Age at diagnosis and diagnostic delay across attention-deficit hyperactivity and autism spectrums. Australian & New Zealand Journal of Psychiatry, 58(2), 142–151. DOI 10.1177/00048674231206997

16. Rong, Y., Yang, C.J., Jin, Y. & Wang, Y. (2021). Prevalence of attention-deficit/hyperactivity disorder in individuals with autism spectrum disorder: A meta-analysis. Research in Autism Spectrum Disorders, 83, 101759. DOI 10.1016/j.rasd.2021.101759

17. Hollingdale, J., Woodhouse, E., Young, S., Fridman, A. & Mandy, W. (2020). Autistic spectrum disorder symptoms in children and adolescents with attention-deficit/hyperactivity disorder: a meta-analytical review. Psychological Medicine, 50(13), 2240–2253. DOI 10.1017/S0033291719002368

18. Grattan Institute, Saving the NDIS, 29 June 2025. https://grattan.edu.au/report/saving-the-ndis/

19. OECD, Policy Responses to Rising Autism Diagnoses in Childhood, 25 March 2026. DOI 10.1787/08394255-en