top of page
Crawling Toddler

Getting an
Autism Diagnosis

Navigating the diagnosis process can be tricky. We've created this resource to help answer questions you may have. If you need any help, you can reach out to our team anytime. 

Did you know? Autism can be diagnosed in children aged from 18 - 24 months but can sometimes be diagnosed even younger.

Steps to getting a diagnosis and support for Autism Spectrum Disorder

Talk to your GP and key supports about your concerns

Get a referral and a formal assessment

If you have concerns about your child's development, we recommend talking to your GP or healthcare professional. You can also complete free screening tools such as the MCHAT above or talk to other key supports like daycare educators who may also have observations that can be helpful when raising your concerns.

Your GP should be able to support you with getting a referral for a formal Autism assessment at different services in your area. An assessment may be run by a public or private provider - Your GP should be able to provide different options based on your family circumstances. Waitlists may vary greatly so ask questions and call around. It may take some time before your child is able to schedule an assessment.

Start accessing support

You do not need a diagnosis to access support or early intervention. Waitlists for formal Autism assessments can be lengthy at times but that doesn't mean you need to wait to get started learning about and supporting your child. A developmental assessment  may be able to be completed while you are waiting for a formal diagnostic assessment, which can give you a good starting point.

Kids in Slide

Do you have concerns about your child's development?

If so, you can start by completing the Modified Checklist for Autism in Toddlers, Revised, with Follow-Up (M-CHAT-R/F).  If your child screens positive on the M-CHAT, it is strongly recommended that your child is referred for early intervention and diagnostic testing as soon as possible. Regardless of the score, if you have any concerns, you may consider discussing this with your child’s GP, paediatrician, or child health nurse. We are also able to provide and assessment of your child's developmental* needs during our initial assessment.

*Please note we do not conduct diagnostic testing and are not able to provide you with a diagnosis  

Kids Playing with Lego

Tip: If you are put on a waiting list for assessment, use that time to read more about the next steps following a diagnosis, or what to do when your child does not receive a diagnosis.

The Diagnostic Assessment Process

There are two sets of Autism Spectrum Diagnostic criteria commonly used throughout Australia:  

The main criteria used is the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders (currently in its fifth edition – DSM-5). The DSM-5 requires professionals to assess for the symptoms of Autism and the impact these have on your child’s life. Symptoms are identified in two ‘domains’ – social communication and social interaction, and restricted and repetitive behaviours. It requires consideration of co-occurring diagnosis. This information can help clinicians in their diagnostic decision-making and identification of support needs.  

The World Health Organisation’s International Classification of Diseases (currently in its 11th edition – ICD-11). The ICD-11 requires clinicians to specify the presence and extent of intellectual and language impairment, along with the impact on numerous areas of functioning.  

Who can diagnose Autism?

Autism assessments may be completed by a single qualified professional, or by a multidisciplinary assessment team.


It is best practice to have input from at least two professionals when assessing for Autism. Currently, in some states and territories, at least two different types of qualified professionals are required to form an Autism Diagnosis, e.g., a Speech Pathologist and a Psychologist. 


The following professionals may be qualified to be involved in an Autism Assessment in a multi-disciplinary team according to the National Guideline for the Assessment and Diagnosis of Autism Spectrum Disorders in Australia.  

Keep in mind, only qualified, trained professionals can make an Autism diagnosis.


  1. Paediatrician. A paediatrician is a doctor who specialises in treating children. Make sure you request a paediatrician who has additional Autism assessment training.  

  2. Psychiatrist. A psychiatrist is a medical doctor who is an expert in mental health. Make sure you request a psychiatrist who has additional Autism assessment training.  

  3. Psychologist. A psychologist is a person who studies the human mind and tries to explain why people behave in the way they do. Make sure you request a psychologist who has additional Autism assessment training.

What should I expect in the assessment?

Depending on your child’s needs, the health professionals you have been referred to will gather information about your child’s medical and health history as well as the following:


  • Developmental and educational history: You will be asked about your child’s development over their lifetime. This may cover a wide range of developmental areas.  

  • Autism-specific signs and/or symptoms: You will be asked about behaviours relating to social communication and interaction and restricted, repetitive patterns of behaviour.  

  • Other relevant behaviours, signs and/or symptoms: You will be asked to indicate whether your child has a co-occurring condition and/or differential diagnosis.

Often, health professionals will use games, puzzles and activities to measure and observe your child’s development.

​ They analyse language skills, social interactions, and sensory aspects.

Sometimes your child will be seen by a range of professionals on the same day, in the same place. This generally occurs when an assessment is conducted in a government service such as a Child Development Unit, or when conducted in an organisation. Sometimes you will see only one health professional. This generally occurs when an assessment is completed in private practice by a qualified professional. Sometimes you may only need one positive assessment to receive an Autism diagnosis. At other times, you may need to complete two Autism assessments by two different types of professionals to receive an autism diagnosis.


It is important to note that in some instances, the requirements to access funding and support will be different from the requirements to receive a formal diagnosis of Autism Spectrum Disorder (ASD). Once your child’s assessment process has been completed, you will generally receive a written report within a few weeks


What questions should I ask?

Just as professionals ask lots of questions, so can you. Here are just a few ideas of questions you may like to ask healthcare professionals throughout the assessment process:  

  1. What is going to be involved in getting an assessment?  

  2. How much will it cost?  

  3. How long will it take?  

  4. When will I find out if my child has Autism?  

  5. Will a report be developed? Will I get a copy? How long will this take?  

  6. Will the report be passed on to anyone else?  

  7. Will the assessment give information about my child’s strengths, and how can they be maximised?  

  8. What specific strategies or interventions should I try at home?  

  9. Are there any other assessments that might be useful?  

  10. How will the results influence the support I can access for my child?  

  11. Do you have any articles or resources on Autism?

My child has just been diagnosed with Autism. Now what?

If your child is diagnosed with Autism, you may have many questions following your assessment. Chances are you will want to learn more about Autism, want to know how to access services and support, and perhaps join a support or Autism group.


Post-diagnostic support is important. The assessor, or the organisation that your child was assessed in, may be able to offer follow-up services after your diagnosis and might be able to answer your questions and point you towards support services for your child. For example, you may be able to access:

  • A post -diagnostic meeting, providing information about what autism is, supports and services and strategies and interventions.  

  • Training and workshops to learn more about autism.  

  • Services such as counselling, a psychologist or other professionals for your child.  

  • Online or face-to-face support groups.  

Parents and Daughter

We're here to help

Scarlett's Autism Therapy Centre is committed to helping children who may require extra support. Whether you are at the start of your journey and still learning about your child's needs, or already have a diagnosis, we'd love to chat with you about how we might be able to provide you with indivdualised support.

bottom of page