Child autism rate is 25 times accepted figure, study warns

Childhood autism is much more widespread in Britain than previously thought, according to a comprehensive survey of school-age children published today.

Doctors at St Thomas' hospital in London screened children aged nine and 10 and diagnosed autism or related disorders in more than 1%. The figure suggests autism is 25 times more common than the four to five cases per 10,000 people widely accepted in the 1990s.

Writing in the Lancet, Professor Gillian Baird, who led the study, called for local authorities to acknowledge the additional support people with autism spectrum disorders (ASDs) require. "Services in health, education and social care will need to recognise the needs of children with some form of ASD, who constitute 1% of the child population," she said.

The study sheds no light on whether the number of children born with autism is rising. Instead, the higher levels are believed to reflect a large number of cases that would previously have gone unrecognised.

Autism is diagnosed using behavioural and psychological tests, but the criteria have broadened in recent years as doctors have included related disorders such as Asperger's syndrome.

"The core feature is an impairment in social interaction, so there's a difficulty with social relationships, and that can range from being withdrawn and aloof to simply not fitting in very easily," said Prof Baird. "In previous years, most children who had a diagnosis of autism would perhaps have some learning difficulties, but we're now recognising autism in young people who don't have learning difficulties and indeed are very capable."