A National Guideline for the Assessment and Diagnosis of Autism Spectrum Disorder in Australia

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Developed and published by Autism CRC with the financial support of the National Disability Insurance Agency (NDIA), the Guideline aims to create greater consistency in diagnostic practices across the country to ensure individuals on the autism spectrum and their families can receive the optimal clinical care.

The Guideline also emphasises the importance of listening to individuals and their families about the impact of the behaviours on family life.
The community has been requesting a national and consistent guideline for autism assessment and diagnosis for many years, and we are pleased to release a guideline that responds to this need. The guideline recommendations were approved by Australia’s National Health and Medical Research Council.


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Frequently Asked Questions

You can receive a copy of the Guideline by registering here. As soon as you have registered, you will receive an email containing a link to download the Guideline and key supporting documents.

The Guideline outlines a step-by-step process for conducting a Comprehensive Needs Assessment and a Diagnostic Evaluation of autism, from the time of referral until the results are shared in a written report.

The Guideline outlines processes for both diagnostic decision-making and the comprehensive assessment of individual support needs. An accompanying Administrative and Technical Report provides detailed information on the guideline development process and the Evidence Tables outlines the evidence supporting the recommendations made in this Guideline.

Autism spectrum disorder (ASD) is a developmental disorder in which individuals show difficulties with social and communication skills, and display a variety of repetitive behaviours. The behavioural features that characterise ASD are often present before three years of age but may first become apparent during the school years or later in life. The signs and/or symptoms of ASD can vary widely in nature and severity, and may be accompanied by mental and physical health problems.
There is no biological test for ASD. Rather, ASD is diagnosed by trained health professionals, who observe an individual for specific behaviours relating to social communication and restricted/repetitive behaviours and interests.
In Australia, a referral for more detailed health and medical assessments is provided by a primary healthcare provider, such as a GP or child health nurse. Your primary healthcare provider will refer you to a health professional who has expertise in the assessment of behavioural and neurodevelopmental conditions.
The Guideline recommends that a Comprehensive Needs Assessment and a Diagnostic Evaluation are conducted.

The number of sessions and the health professionals involved may differ according to a range of factors, such as the presentation of the individual being assessed, their geographic location and the organisation in which the assessment is conducted.

The guideline describes an evidence-based process for the assessment and diagnosis of Autism Spectrum Disorder. The guideline will help you understand this process, and the information can help you ensure that you are receiving appropriate clinical care.
The guideline does not change the status of existing diagnoses. You do not need to have another diagnostic assessment as a result of the publication of the guideline. The guideline describes a process that is recommended for current and future clinical practice.
The guideline describes an evidence-based process for the assessment and diagnosis of Autism Spectrum Disorder. If you have queries about the diagnostic process you went through, or the publication of this guideline, then it is recommended that you discuss and ask questions of the clinical team that conducted the diagnostic assessment, or seek a second opinion.
If the clinical team that conducted the previous diagnostic assessment has suggested you/your child is reassessed in the future, it is recommended that this future assessment utilise the process described in the guideline.
The approval of the guideline recommendations by the National Health and Medical Research Council indicates that the process outlined in the guideline is considered optimal clinical practice in Australia. To ensure that all clients receive best clinical care, it is suggested that you adopt the recommendations outlined in this guideline as soon as practical.
No. The guideline has been developed specifically for Australia, and incorporates sufficient flexibility to enable the recommendations to be adapted to the wide variety of contexts across the country.
While it is not mandatory for clinicians to follow the consensus-based recommendations outlined in the guideline, a critical next step is for a coordinated implementation project that supports the clinical community and government departments to adopt the recommendations.

The purpose of the Comprehensive Needs Assessment is to understand the strengths, challenges and needs of the individual being assessed. This assessment consists of two parts: an Assessment of Functioning and a Medical Evaluation.

Assessment of Functioning

The purpose of this assessment is to obtain a detailed understanding of an individual’s level of ability across a broad range of areas, including cognitive abilities, speech and language function, and daily living skills. Some of the information collected during this assessment will be about:

  • medical and health history
  • family history
  • developmental and functional abilities.

An Assessment of Functioning can be performed by one or more medical and/or allied health professionals. This could be a medical practitioner (e.g. GP, paediatrician, psychiatrist), nurse practitioner, occupational therapist, psychologist, social worker or speech pathologist with relevant training and expertise.

Medical Evaluation

The purpose of this evaluation is to understand if there are medical causes for the behaviours that have prompted a referral for an assessment. A Medical Evaluation involves: 

  • a general physical examination
  • other specific medical tests.

A Medical Evaluation is completed by a medical practitioner, such as a paediatrician, psychiatrist or GP.

The purpose of a Diagnostic Evaluation is to understand if an individual’s behaviours are consistent with a diagnosis of ASD and/or another condition. It involves:
  • a review of previously collected information
  • an interview with the individual and/or their caregiver
  • an assessment of the signs and symptoms for ASD and other related conditions
  • assessments of related behaviours, such as cognitive ability, and speech and language skills.
A Diagnostic Evaluation may be conducted by a single clinician with a specified medical or psychology background, or they may invite a team of clinicians to make a consensus diagnostic decision. Which professionals are involved will depend on a range of factors, such as the type and complexity of the medical and/ or behavioural symptoms that the individual is showing. All the professionals involved will have skills and experience in the assessment of ASD and related conditions.
A written report will be given to the individual who has been assessed and/or their caregiver, and the health professionals will explain the content of the report in a meeting. The report will summarise the information collected during the Comprehensive Needs Assessment and Diagnostic Evaluation, explain what this information means, provide a rationale for any diagnostic decision made, and suggest next steps.
For more information, please contact Autism CRC on 07 3377 0600 or info@autismcrc.com.au.


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The Artwork


Artwork by Dr Emma Goodall


We thank Dr Emma Goodall for providing the cover art for the National Guideline.

The artwork is titled The Disconnect in the Infinity of Neurodiversity. Artist Dr Emma Goodall describes the artwork below.

"Hidden under the layers of the ¾ of an infinity symbol are a normal distribution curve, a brain and branches seeking connection from a brain/person to an anchor. The ¾ infinity symbol also more explicitly shows the variety within the spectrum but the gaps in knowledge and connections."