Getting an autism diagnosis for adults

The most interesting people you’ll find are ones that don’t fit into your average cardboard box. They’ll make what they need, they’ll make their own boxes.
— Dr Temple Grandin, Autism Advocate

So you want to be assessed for autism?

There are a number of ways that you may have arrived at this decision. It may be that your child has been diagnosed as autistic and you recognise a few behavioural similarities. Perhaps your significant other or a close friend has suggested that you are autistic? Or perhaps you’ve had the feeling of ‘being different’ and have long suspected you might be on the spectrum?

Whatever the reason, the following page will help you to prepare for an assessment, and give you more information about what to expect.

Autism assessment and diagnosis for adults

Getting started

Your first port of call if you want to be assessed for autism could be:

Making an appointment to see your General Practitioner (GP).
Talking to a psychologist.
Self-referring directly to a qualified professional or organisation that can undertake autism assessments.

Where to get an assessment

There are a number of government-funded services that specialise in the assessment and diagnosis of autism. You can contact these teams directly, but you may need a referral from your GP.

There are also private practitioners and organisations that conduct assessments on a fee-paying basis. These services can be accessed via a referral from a health care professional, or you may be able to refer yourself directly.

Quick tip: It is important that you are assessed by a qualified professional with a comprehensive understanding of autism across ages and has practical experience with the assessment and diagnosis process.

To learn more about professionals experienced in the assessment and diagnosis of autism, go to our Support and services section.

Assessment process

The diagnostic criteria for autism in adults and children is the same, however the ways characteristics are assessed against the criteria can be quite different depending on your age.

What diagnostic criteria is used?

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 a person’s life. Symptoms are identified in two ‘domains’ – social communication and social interaction, and restricted and repetitive behaviours. It requires a range of considerations, including 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.

What does it cost to get an autism assessment?

The out-of-pocket cost of any assessment will depend on a number of factors, including:

Whether you are referred to a health professional in the public or private health system.
Whether you have private health cover – and the level of that cover.
Your personal financial circumstances and whether you are receiving certain Centrelink payments.

You can check with your medical professional directly as to any costs involved.

Find out more in our Financial support page.

How do professionals make an autism assessment?

Assessment tools often use a series of questions, in-person observations and interactions to support a professional diagnosis of autism.

Depending on your needs, health professionals will gather information around your medical and health history as well as the following:

Developmental and educational history: You will be asked about your development as a child and teenager. This may cover a wide range of developmental areas.
Autism-specific characterisitics: You will be asked about behaviours relating to social communication and interaction and restricted, repetitive patterns of behaviour.
Other relevant behaviours or characteristics: You will be asked about the presence of any co-occurring condition and/or differential diagnosis.

Quick tip: Sometimes, it may be helpful to invite someone who knew you as a child to your appointment – perhaps an older sibling, childhood friend or a parent. They may be able to offer important information about your early childhood that you don’t remember. However, this is entirely up to you.

The professional may also discuss your mental health. It is important that you answer these questions as honestly and openly, so that your assessor can get a full understanding of your health. According to the National Guideline for the Assessment and Diagnosis of Autism Spectrum Disorders in Australia, a range of mental health conditions are common among autistic adults. These can include depressive disorder, anxiety disorders (such as social anxiety disorder and obsessive-compulsive disorder) and thoughts of suicide. If you are experiencing symptoms of any of these conditions, your doctor will be able to refer you to appropriate professionals for further investigation.

Quick tip:
You know yourself best. If your GP or other health professional doesn’t feel you warrant further assessment – but you feel you do – get a second opinion.

Questions to ask

Just as professionals ask many questions, so can you. You may want to ask your doctor, or a professional, some of the following questions:

What is going to be involved in getting an assessment?
How much will it cost?
How long will it take?
When will I find out if I am autistic?
What will happen if I am autistic? What will happen if I am not autistic?
Will a report be developed? Will I get a copy? How long will this take?
Will the report be passed onto anyone else?
Will the assessment give information about my strengths and how can they be maximised?
Is there any other assessments that might be useful?
How will the results influence the support I can access?
Do you have any articles or resources on autism?

Quick tip: Don’t forget to take a pen and note pad along with you so you can revisit their answers, or discuss the outcomes with friends, family, or other professional service providers in the future.

When will I get my result?

The qualified assessing professional (or professionals) that you choose to see will advise whether they think you are autistic, or not. They might do this on the day of your assessment, or at a follow-up appointment. A written report should be provided after the assessment.

Make sure you ask them how they will deliver the information so you know what to expect and can follow up if needed.

I have been diagnosed as autistic – what next?

If you are diagnosed following your assessment you may have a lot of questions. Chances are you will want to learn more about autism, want to know how to access services and support, and perhaps join a support group.

Post-diagnostic support is important. Your assessor, or the organisation that you were 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 example, you may be able to access:

A post diagnostic meeting providing information about what autism is, supports and services and strategies and programs.
Training and workshops to learn more about autism.
Services such as counselling, a psychologist or other professionals.
An online support group or social group for autistic adults.
Vocational support around employment, education or other areas.

You can learn more about support and services available to you in our Support for autistic adults page.

I have not been diagnosed as autistic – what next?

You may feel frustrated by going through the assessment process and not getting a diagnosis. Or you may feel confused and not know what to do next.

The professional conducting the autism assessment will be able to provide information about why you did not meet the criteria to be diagnosed with an Autism Spectrum Disorder (ASD) either face-to-face or over the phone, and may also provide you with a written report.

The assessing professional may be able to provide further information, any other assessments that might be beneficial, or refer you to other supports and services.

Professionals conducting autism assessments are guided by a very specific criteria, and must adhere to professional standards of practice. They need to ensure these are upheld when conducting an autism assessment and generally take considerable time reviewing all the information before making a decision.

If you disagree with the outcome, it is best to discuss this with the professional who made the assessment, and listen to the reasons why this was the case.

If you still disagree, you have the right to get another autism assessment completed with a different professional.

For more information or support, visit our page Help following a diagnosis.

Autistics’ Guide to Adulthood

Autistics’ Guide to Adulthood is an online life-skills resource to support people to achieve their goals. It’s free and available to anyone who would like to learn more about adulthood.

Click here to learn more about this resource.