What to Expect During an Autism Diagnostic Assessment: A Guide for Parents

When you first begin the journey of exploring whether your child may be on the autism spectrum, the process can feel overwhelming. Parents often have questions such as: Who will assess my child? What will happen during the appointment? How long will it take? Knowing what to expect during an autism diagnostic assessment can make the experience less stressful and help you feel prepared to support your child every step of the way.

This guide will walk you through the basics of the autism diagnostic process, including who conducts the assessment, what typically happens before and during the evaluation, and what you can expect afterward.

Who Conducts an Autism Diagnostic Assessment?

An autism diagnostic assessment is typically carried out by professionals who specialize in child development and neurodevelopmental differences. Depending on where you live and the age of your child, the team may include:

• Developmental Pediatricians – doctors trained in identifying developmental delays and differences.
• Child Psychologists or Neuropsychologists – experts in testing and evaluating developmental, learning, and social-emotional functioning.
• Speech and Language Pathologists (SLPs) – who evaluate communication, language, and social use of language.
• Occupational Therapists (OTs) – who may assess sensory processing, motor skills, and daily living abilities.
• Multidisciplinary Teams – many clinics use a team approach where several specialists collaborate to gather a complete picture of your child.

The specific professionals involved may vary, but the goal is always the same: to understand your child’s strengths, challenges, and developmental profile as clearly as possible.

What Happens Before the Autism Diagnostic Assessment?

Before your child’s appointment, you will usually be asked to complete forms and questionnaires. These may include:

• Developmental History Forms – questions about your child’s milestones, medical history, family history, and any concerns you’ve noticed.
• Behavior and Symptom Questionnaires – standardized tools where you rate your child’s behavior, social interactions, communication, and routines.
• Teacher or Caregiver Input – many evaluators ask for feedback from teachers or daycare providers to see how your child functions in different settings.

This background information helps the assessment team understand your child’s day-to-day experiences and guides what they look for during the evaluation.

What Happens During the Assessment?

The diagnostic assessment itself can look different depending on your child’s age and the clinic’s approach. However, most assessments include several key parts:

1. Parent Interview

A clinician will sit down with you to ask about your child’s history, strengths, and areas of concern. This is often based on a structured tool, such as the Autism Diagnostic Interview – Revised (ADI-R). Expect questions about early milestones, communication, social behavior, play, routines, and sensory responses. Parents are the experts on their children, so your input is essential.

2. Child Observation and Interaction

Your child will participate in activities designed to show how they communicate, play, and interact socially. A common tool used is the Autism Diagnostic Observation Schedule (ADOS). Depending on your child’s age, this might involve playing with toys, looking at pictures, having conversations, or completing simple tasks. The clinician observes:

• How your child uses eye contact, gestures, and facial expressions.
• How they respond to social cues.
• How they play with toys and use their imagination.
• Their ability to start or maintain interactions.
• Any repetitive movements, behaviors, or strong interests.

3. Cognitive and Developmental Testing

Some assessments include testing your child’s learning style, problem-solving, and memory. This could be formal IQ testing, academic testing, or developmental scales for younger children.

4. Speech, Language, and Motor Assessments

If needed, specialists may look closely at your child’s ability to understand and use language, as well as fine and gross motor skills.

How Long Does the Assessment Take?

The length of an autism diagnostic assessment can vary widely depending on the clinic, your child’s age, and the tools used. Some assessments may take two to three hours in one day, while others are spread out over multiple sessions lasting several hours each.

In some cases, particularly in hospital or university-based clinics, the process can take place over several days to allow for thorough testing and team collaboration.

Be prepared to bring snacks, comfort items, and breaks for your child if the session is long.

What Happens After the Assessment?

After the evaluation is complete, the clinicians take time to review all of the data collected. This may include their observations, test results, your input, and feedback from teachers or caregivers. The next steps typically include:

1. Feedback Session

You will meet with the clinician (or team) to go over the findings. They will explain:

• Whether your child meets criteria for an autism diagnosis.
• Your child’s strengths and areas for support.
• Any additional diagnoses or concerns identified.
• Recommendations for therapies, school supports, and community resources.

This session is your opportunity to ask questions and get clarity. Many parents feel a range of emotions, such as relief, sadness, or even confusion. All of these feelings are normal.

2. Written Report

You will receive a detailed written report summarizing the evaluation. This is an important document you may need to share with your child’s school, therapy providers, or insurance.

3. Referrals and Next Steps

If your child is diagnosed with autism, you will likely be referred to early intervention services (for children under 3), school-based supports (for children 3 and older), or therapies such as applied behavior analysis (ABA), speech therapy, or occupational therapy.

Even if your child does not receive an autism diagnosis, you may still get recommendations for supports that can help with communication, learning, or social-emotional development.

Tips for Parents Preparing for the Assessment

• Write down your observations. Keep a list of behaviors, strengths, and concerns to share with the clinician.
• Gather records. Bring copies of previous evaluations, school reports, or medical records.
• Prepare your child. Explain in simple terms that they’ll be meeting with people who want to play, talk, and learn more about them.
• Take care of yourself. This can be an emotional process, so bring support if you need it.

Autism Diagnostic Assessments

An autism diagnostic assessment is an important step in understanding your child’s unique needs and supporting their growth. While the process may feel overwhelming at first, it is designed to give you clear answers and open the door to services that can make a meaningful difference.

Remember, a diagnosis is not a label that defines your child; it’s a tool that helps you access the right supports and celebrate your child’s strengths. Whatever the outcome, you are taking a positive step by seeking clarity and support for your child.