What Autism Questionnaires Are Used During Diagnosis?

This guide explains the main autism assessment questionnaires, who they're for, what they measure, and why a score alone can never diagnose autism.

There's no blood test or scan for autism. Instead, clinicians build a detailed picture of someone's life, from early childhood to now.

Questionnaires are one part of that picture. They help your clinician:

• see which autistic traits might be present
• understand how things affect daily life
• spot anything else that might need support, such as anxiety
• compare views from different people, such as parents and teachers
• focus your assessment time on what matters most

The AQ-10 is a short version of the Autism Spectrum Quotient. It has 10 questions, and is recommended in NICE guidelines as a quick screening tool for adults.

Who it's for: there are versions for adults, which you complete yourself, and for teenagers and children, which a parent or carer completes.

What it measures: it asks how much you agree with statements about everyday experiences, such as:

• noticing small details others might miss
• finding it hard to work out what someone is thinking or feeling
• preferring routines, or finding it hard to switch between activities
• finding social situations easy or difficult

What it can tell your clinician: a higher score suggests autistic traits may be worth exploring further. But it's only a screening tool, and can't confirm or rule out autism.

You may also come across longer questionnaires for adults, such as the RAADS-R, which work in a similar way and are also used alongside a full assessment.

The CAT-Q (Camouflaging Autistic Traits Questionnaire) looks at masking, also called camouflaging. This is when someone hides or works around autistic traits, often to fit in.

Who it's for: adults and older teenagers, completed by the person themselves.

What it measures: it looks at three areas:

• compensation: using learned strategies to manage social situations, such as practising conversations in advance
• masking: hiding autistic traits, such as forcing eye contact
• assimilation: trying to blend in with others, even when it feels uncomfortable

Why it matters: many people, especially women and girls, mask so well that their autistic traits are missed. The CAT-Q helps your clinician understand what's going on beneath the surface, which other questionnaires might not pick up.

The SDQ (Strengths and Difficulties Questionnaire) is a short questionnaire about a child or young person's wellbeing and behaviour.

Who it's for: children and young people. It can be completed by parents, teachers, and young people themselves from around age 11.

What it measures: it covers five areas:

• emotional difficulties, such as worries
• behaviour
• attention and restlessness
• friendships and getting on with others
• kind and helpful behaviour, which are strengths

Why it matters: the SDQ isn't specific to autism. Instead, it gives a broad picture of how a child is getting on at home and at school, and can highlight other needs. Comparing parent and teacher views also shows whether difficulties appear in more than one setting.

The RCADS (Revised Child Anxiety and Depression Scale) looks at anxiety and low mood in children and young people.

Who it's for: children and young people, usually aged around 8 to 18. There's a version for the young person and a version for their parent or carer.

What it measures: different types of anxiety, such as social worries, separation anxiety and general worry, as well as low mood.

Why it matters: anxiety and low mood are common in autistic young people. They can also look similar to some autistic traits. The RCADS helps your clinician understand what's going on, so the right support can be recommended.

It's natural to want to know what a score means. But no questionnaire can diagnose autism on its own, because:

• masking can lower scores. People who hide their traits well may score lower than expected.
• other things can raise scores. Anxiety, trauma, ADHD and other conditions can affect answers.
• context matters. A questionnaire can't show whether traits have been there since early childhood.
• some questionnaires aren't about autism at all. The SDQ and RCADS look at wellbeing, behaviour and mood, which help build the full picture.

That's why your clinician brings questionnaires together with a developmental history interview, such as the ADI-R, and an observation, such as an ADOS-informed session. In line with NICE guidelines, the final decision uses DSM-5 or ICD-11 criteria.

• There are no right or wrong answers. Answer based on how things usually are.
• Don't overthink it. Your first response is often the most accurate.
• Take breaks. You can complete them in chunks.
• Be honest about masking. Think about how things feel inside, not just how they look to others.
• Ask for help if a question is unclear.

Raiys works nationwide, offering online autism assessments for adults, and for children and young people, across the UK. You'll complete your questionnaires securely through your Raiys portal before your appointment. For children's assessments, we also ask school to share their views, so we get a full picture.

If you're in crisis right now, call 999, go to A&E, or call Samaritans free on 116 123, any time of day or night.

Ready to take the next step? Find out more about our autism assessments.

Questionnaires are just one part of the process. Your answers help start the conversation, and the full assessment is where your story, or your child's, is properly understood.