Dame Uta Frith warns that the expanding autism spectrum risks obscuring critical differences, urging for clearer subgroups and standards to better serve those with severe difficulties and avoid overgeneralisation.
Autism may no longer fit neatly inside a single diagnostic box, according to Dame Uta Frith, who argues that the modern spectrum has widened so far that it risks obscuring the very differences it was meant to capture.
Writing in Psychological Medicine, the UCL professor says autism now describes people whose lives can look profoundly different. Some need lifelong help with communication, personal care and daily routines. Others live independently, work, study and may not be identified until adulthood.
That breadth reflects decades of change in how doctors understand autism. In the 1940s, early clinical descriptions focused on children with striking differences in social interaction, communication and behaviour. Over time, diagnosis expanded to include people without intellectual disability or major language difficulties, eventually becoming autism spectrum disorder.
The word “spectrum” was meant to acknowledge that diversity. Frith’s point is that the category may now be so broad that it covers people with very different development, support needs and daily experiences under the same label. She argues that the result may be useful for recognition, but less helpful for precision.
The rise in diagnoses has sharpened that debate. Frith cites British research from the 1960s that put autism at about four children in every 10,000, compared with current figures suggesting roughly 1 in 57 UK schoolchildren is identified as autistic. She says that does not prove autism has become dramatically more common, since better awareness, reduced stigma, changes in diagnostic practice and improved detection all push numbers higher.
She also points to more contested explanations, including broader reading of diagnostic criteria, self-identification and a culture more willing to frame personal struggles in medical terms. Yet diagnosis remains a clinical judgement, not a blood test or brain scan, which means assessments depend on development history, observation and professional interpretation.
That can be especially difficult when autism-like traits overlap with anxiety, depression, attention deficit hyperactivity disorder, trauma or personality differences. Frith also notes a growing divide between those diagnosed in early childhood and those identified later, often as teenagers or adults, with the latter group more likely to have average or above-average intelligence and to present first with anxiety, exhaustion or social difficulties.
Some research has suggested genetic and developmental differences between those diagnosed at different ages. Frith says that should prompt scientists to ask whether the spectrum contains distinct groups that deserve separate study. She makes a similar point about masking, the effort some autistic people make to hide traits to fit in. While that concept has helped explain missed diagnoses, she warns that broad, loosely defined terms can make the diagnostic boundary harder to defend.
The wider argument sits squarely within the neurodiversity movement, which has helped challenge stereotypes and pushed for greater acceptance of neurological difference. Frith does not argue for stripping people of diagnosis or support. Instead, she calls for clearer subgroups, sharper diagnostic standards and greater attention to the people with the most severe difficulties.
Her warning is best read as a demand for precision rather than a simple claim of overdiagnosis. Broader definitions have also helped many people, especially women, adults and those without intellectual disability, to find explanations and support after years of being overlooked. The question she raises is whether one label can still do enough work for both science and care.
Disclaimer: This content is for informational purposes only and is not intended to be a substitute for professional medical judgment, advice, diagnosis, or treatment.
