Here's what you can expect to happen on the day of the autism assessment and soon after. 

On the day 

The diagnostic team is made up of people from different professions. They are likely to assess your child separately, and the individual findings will be used by the team leader to inform the diagnosis. This may mean you need to go for several appointments and it may be some time between appointments. 

Different diagnosticians use different methods to diagnose autism, but there are guidelines that they should follow: 

• NICE Clinical Guideline 128 in England, Wales and Northern Ireland 

• SIGN Clinical Guideline 145 in Scotland. 

An assessment usually includes:  

• reports from all settings (eg school, nursery)

• an autism-specific developmental and family history

• observations in more than one setting

• communication, behaviour and mental health assessments

• a physical examination

• tests and assessments for other conditions where appropriate. 

The team should explain to you the reason for each test or assessment. 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 diagnostic report 

The diagnostician will tell you whether or not they think your child is autistic. They might do this on the day of the assessment, by phone on a later date, or in a written report that they send to you in the post. 

Diagnostic reports can be difficult to read and understand in places. You can call the diagnostician to talk through any parts of the report that you find unclear. They are also very deficit-based, detailing what the child cannot do, which can be upsetting reading for parents. 

The report should give a clear diagnosis. Phrases such as ‘has autistic tendencies’ are not very helpful because they imply that a child is not autistic. This can cause problems when trying to access autism-specific support. 

It is very important to understand your child's individual profile of needs. The report may say that your child presents a particular autism profile, such as an Asperger syndrome or demand avoidant profile, and may give recommendations for support. 

If you don’t agree with the diagnosis 

You may be told that your child is not on the autism spectrum, or your child may be given a diagnosis that you don’t agree with. 

You can seek a second opinion, which either means going back to the GP to explain that you aren't happy with your diagnosis and ask them to refer your child elsewhere, or paying for a private assessment. 

If you go for a second assessment, remember that it may reach the same conclusion as your first. 

Being referred to a specialist service 

If they feel that your child presents a complex case, the professional or team who did the assessment may refer your child on to a tertiary level service (a specialist level of health care), such as our charity’s Lorna Wing Centre for Autism. Funding issues can often delay the process of getting a second opinion. There may be no tertiary service in your local area. In some cases, funding for out-of-area referrals is refused. 

Complaints 

You have the right to complain if you're not happy about any aspect of referral, diagnosis or care that your child has received from an NHS service. The complaints procedure is different in each UK nation. 

If you have a complaint about a private diagnostician, they should have their own complaints procedure, as required by the Care Standards Act 2000. 

Useful links 

• Helpline and advice services 

• Family support services 

• Our online community, a place to share your thoughts and experiences

• Our Autism Services Directory for local parent groups and our branches.  

Next steps 

• Read more about the criteria for an autism diagnosis
• Find out about post-diagnostic support
• How to talk to your child about autism.