Toddlers found to have autism who undergo intensive teaching programmes from the age of 3 can raise their IQ by as much as 40 points, according to a three-year study.

The research found that intensive, early education, which costs about £30,000 a year per child, also led to “significant positive changes” in language, daily living skills, motor ability and social skills.

The study, conducted by the University of Southampton, will put pressure on the Government to help to fund early intervention for autistic children. It often costs households more than £30,000 a year as one parent is forced to give up work completely to oversee about 40 hours of tuition a week.

Most of the money is spent on hiring tutors and a course supervisor who shapes the programme for the child and assesses its progress.

It is the first major study of its kind in Britain, although thousands of families are known to be using the programme, the best known of which is applied behaviour analysis (ABA). It breaks down learning into tiny chunks, using imitation and reinforcement to encourage autistic children to communicate, then speak and follow commands, before moving on to more advanced skills.

Half the 44 autistic children had the treatment for two years, significantly starting at the age of 30-42 months. That is usually the time at which families who suspect their child may be autistic are struggling to get a formal diagnosis.

The children in the study ranged from the high-functioning, with better communication skills and higher IQs, to the low-functioning with poor speech and few social skills. All had a formal diagnosis of autism.

The researchers found that early intervention was more effective with the higher-functioning children who had a higher mental age and better social skills, although all benefited to some degree.

The first group of children in the study were given 25 hours of one-to-one treatment a week from between three and five tutors, and also from their parents, all using the principles of ABA. This is fewer hours than the 40 a week most parents sign up to.

The control group had received the basic speech or language therapy normally offered by local education authorities.

As well as improved communication and social skills, more than a quarter of the children showed “very substantial improvements” in their IQ. In one case IQ increased from 30 to 70, in another, from 72 to 115. Most of the population has an IQ of between 85 and 115.

“This form of teaching can, in many cases, lead to major change,” said Professor Bob Remington, deputy head of the University of Southampton School of Psychology. “In practice, the positive changes we see in IQ, language and daily living skills can make a real difference to the future lives of children with autism.”

With one in a hundred children thought to be suffering from some form of autism, the costs are potentially very high. However, John Wylie, chief executive of TreeHouse Trust, a school for autistic children, said: “It has to be compared with the cost of looking after someone with autism which conservative estimates put at £3 million over their lifetime. Spending the money at a time when it can make a difference is surely better than pouring it about when it can make little difference.”

What it means to have a child born with autism

Autism is a lifelong disability that affects the way a person communicates and relates to others. It is often accompanied by learning disabilities

Autism is a spectrum disability with varying degrees of severity. It includes Asperger syndrome where sufferers have poor communication skills but often higher-than-average IQs

588,000 people in Britain have some form of autism, with boys four times more likely to develop it than girls

40 per cent of children wait at least three years for a formal diagnosis

21 per cent of children with autism have been excluded from school

There is no cure, and the cause is still being investigated, although some evidence suggests genetic factors are behind various forms of autism

Source: The National Autistic Society

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