A new test for autism which claims to be 100 per cent accurate has been developed by scientists.
The test, which uses scans to measure deviations in brain circuitry, could some day replace the current questionnaire tests now used to identify those with the disorder.
Researchers at Harvard University's McLean Hospital and the University of Utah believe it is the best biologically based test for autism to date.
It could also lead to a better understanding of autism and to earlier and better management and treatments of affected individuals.
"This is not yet ready for prime time use in the clinic, but the findings are the most promising thus far," said Professor Nicholas Lange, a psychiatrist at Harvard Medical School, speaking in The Daily Telegraph.
The test involves an MRI scanner that was programmed to measure microscopic features of the brain's circuitry.
"It provides pictures and measurements of the microscopic fibre structures of the brain that enable language, social and emotional functioning, which can reveal deviations that are not found in those without autism," Professor Lange said.
"There is less directional flow to and from brain regions where there should be more information exchange."
A repeat study using two different sets of subjects showed the same high level of performance.
Future studies will now look at patients with high-severity autism, younger children, and patients with brain disorders such as developmental language disorders, ADHD and OCD, who do not have autism.
If the test demonstrates further success, it could one day replace the current subjective system of diagnosing autism, which is not biologically based.
The study is published in the journal Autism Research.
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