There is no single test for diagnosing autism spectrum disorder (ASD). Diagnosis usually involves a range of tests and measures. Often, it also involves several different specialists and professionals. Although this might seem scary, a combination of tests and professionals can achieve an accurate diagnosis and appropriate treatment plan.
There is no single test available to diagnose ASD. Instead, diagnosis is based on watching how the child plays and interacts with others (current development), interviewing parents, and reviewing the child’s developmental history (past development).
By using a combination of tools, professionals can diagnose a child with ASD, and determine where on the spectrum the child falls.
When diagnosing autism, professionals like psychiatrists and psychologists will refer to the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV-TR). This tool breaks down the signs and symptoms of ASD into categories. It also states how many of these must be present in each category to confirm a diagnosis of ASD in children over three years of age.
Read the DSM-IV-TR criteria for a diagnosis of autism (PDF doc size: 49kb).
A paediatrician, psychiatrist, psychologist, or other trained professional in ASD can diagnose a child with ASD.
You might need a referral to see these professionals, so your GP is a great place to start. Visit our Autism Services Pathfinder to find out more about the steps to diagnosis.
Second opinions
You know your child best. If you have genuine concerns about your child’s development, seek further help. If your paediatrician does not have any concerns about your child, but you’re still worried, get a second opinion.
Other parents can be a great recommendation to help you find the right doctor. Visit our forum for parents of children with ASD to connect with other parents.
Although no test or tool can replace diagnosis by an experienced clinician, there are standardised tools that help clinicians with diagnosing ASD.
Some of the tests and screening measures that can assist in the diagnosis of ASD include:
These tools might not identify every child on the spectrum, especially those who have only milder signs of ASD.
Because other medical difficulties sometimes accompany ASD, your paediatrician might also conduct other tests, such as a physical examination and history, and a hearing test. These tests:
The child should also receive a cognitive assessment (IQ test), which can identify developmental strengths and weaknesses. The assessment will also identify whether your child has an intellectual disability, common in many (but not all) children with autism.
Most children will also have a language assessment undertaken by a speech pathologist.
You might find you are put on a waiting list for assessment. The important thing is not to see this as a period when nothing happens. If you can, look for options – you might be able to get an assessment sooner. The Autism Services Pathfinder can show you all the options for diagnosis. There are also services that will allow you to start programs and therapies without a diagnosis.
Occasionally, the outcome of your assessment might be a recommended period of ‘watchful waiting’. This means your healthcare practitioner wants to wait to see whether your child’s symptoms change with a few more months of development. It’s possible the symptoms might resolve or become more pronounced.
If you’re told to wait and watch, again the key is to be proactive:
For more information on ASD and early intervention options, you could attend a free Early Days workshop in your area. You could also check out RCN’s forum for parents and carers who attend Early Days workshops.
If your child is diagnosed with autism spectrum disorder (ASD), you might go through many feelings and reactions.
As the parents in this video explain, reactions to an ASD diagnosis can include relief, sadness, shock, denial and anger. Everybody’s different, and there’s no one right way to feel. But these parents do say that it’s important to work through your emotions. This way you can start to help your child.
Article developed in collaboration with Cheryl Dissanayake and Cherie Green, The Olga Tennison Autism Research Centre, La Trobe University.
American Academy of Pediatrics (2008). Autism – Caring for children with autism spectrum disorders: A resource toolkit for clinicians. Elk Grove Village, IL: Author.
American Psychological Association (2004). DSM-IV-TR: Diagnostic and statistical manual of mental disorders (4th ed., Text revision). Washington: Author
Autism Victoria (2003). Assessment guidelines and protocol for the identification of autism spectrum disorders. Retrieved November 2008, from http://www.bsdgp.com.au/content/Document/Resources/Prac%20Support/MBS%20Item/assessment-protocol.pdf.
O’Brien, M. & Daggett, J.A. (2006). Beyond the autism diagnosis: A professional’s guide to helping families. Baltimore, Paul H. Brookes.
O’Reilly, B. & Smith, S. (2008). Australian autism handbook: The essential resource guide for autism spectrum disorders. Edgecliff, NSW: Jane Curry Publishing,
Young, R., Brewer, N., & Pattison, C. (2003). Parental identification of early behavioural abnormalities in children with Autistic Disorder. Autism, 7, 125-143.