Diagnosis of Autism

Girl sitting on floorGetting a diagnosis of autism can be a positive thing. It means you have an explanation for some of the difficulties you or your child may be experiencing, and it may also give you access to services and support.

The process of getting a diagnosis varies from country to country and sometimes even within the same country. This page describes the processes within the countries that make up the UK.

In the UK you start the process by contacting your GP, health visitor or SENCO who will then refer you on to specialist diagnostic services. However this is not always a straightforward process, with some professionals being reluctant to start the process and with a lack of specialist diagnostic services in some areas.

The Signs

There is no specific biomarker for autism, such as a blood test. Diagnosis is made on the basis of characteristic behaviours including

  • persistent difficulties with social communication and social interaction.
  • restricted, repetitive patterns of behaviour, interests, or activities.

Early signs of autism in children may include lack of speech, delayed speech, speech which is odd, not responding to other people, not interacting with other people, restricted behaviours and interests, repetitive body movements, or strong reactions to noises, smells or lights.

Women and girls on the autism spectrum may be harder to diagnose because they may appear to be more sociable than men and boys, having learnt to 'mask' their autism.  They are also more likely to be misdiagnosed with other conditions, such as obsessive compulsive disorder.

The Referral

If you would like to get a diagnosis of autism for yourself you should first visit your GP. If you would like to get a diagnosis for your child you can visit your GP or talk to your health visitor. If your child is in school you can also contact the special education needs coordinator (SENCO) in your child's school.

Alternatively you can contact an independent diagnostic service, although you will have to pay for this and the diagnosis may not be accepted by some authorities, such as your local social services or the Department for Work and Pensions.

If your GP or health visitor is satisfied that you or your child may have autism, she will normally refer you on to a specialist service for a formal assessment (diagnosis). You may have to wait some time before you actually go for the assessment.

As an adult with suspected autism, you are most likely to be referred to a psychiatrist or a clinical psychologist. As the parent of a child with suspected autism, you may be referred to a single professional or you may be referred to a multi-disciplinary team of several professionals including, for example, a clinical/educational psychologist, a psychiatrist and a speech and language therapist.

If you happen to know of an experienced diagnostician in your area, you can ask your GP or health visitor to refer you or your child to them. You can also be referred to a service outside your local GP commissioning group but as this costs more, your GP might question why you need to go there, or whether you really need a diagnosis

The Assessment

The process of diagnosis will vary depending on where you live. There isn't one standard way for an assessment to be carried out, but there are guidelines that professionals should be following such as those issued by the National Institute for Health and Clinical Excellence (NICE) - details at bottom of this page.

The people who carry out the assessment may use a variety of diagnostic 'tools', checklists and observations, and ask you lots of questions, in order to make their diagnosis.

Please remember: A diagnosis is not a medical examination: you don't need to be examined physically and shouldn't be asked for any samples, such as blood

During the assessment(s), you should be given plenty of time to ask questions. Don't be afraid to ask for explanations or clarification if you need them.

The Report

Sometimes you'll receive a diagnostic report (which is the formal diagnosis) at the end of the assessment. At other times it is typed up and sent in the post. If this is the case, you might have to wait a while before the report arrives.

Ideally, you'll get a detailed report containing both the diagnostician's findings and recommendations for support.

Diagnostic reports can be difficult to read and understand in places. They may use language that diagnosticians are familiar with but that you might not be. You can call the diagnostician to talk through any parts of the reports that you aren't clear about.

The Outcome

If you receive a formal diagnosis of autism, the person making the diagnosis should share information from the assessment with your GP. You should also be offered a community care assessment by your local authority. This assessment should be comprehensive and should include consideration of your needs inc: personal/social care, health, accommodation, finance, education/employment/leisure, transport/access, any communication, psychological or other needs.

For more information please see Services for adults with autism

If your child receives a formal diagnosis of autism, the diagnostic team should share information from the assessment with your child's GP and, if you agree, with other professions such as your child's school or social services if appropriate, to help them offer you the support you need

For more information please see Services for children and young people with autism


If your GP decides not to refer you or your child for a diagnosis, ask for the reason why. If you don't feel comfortable discussing their decision then and there, you can ask for a second appointment to talk it through.

There is a complaints procedure you can follow. See the NHS complaints procedure - details at the bottom of this page. 

Assessment and Diagnostic Services

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27 May 2022