How to Prepare for an Autism Assessment in Ontario

Create a written timeline of your child's developmental milestones: when they first smiled, babbled, pointed, walked, spoke first words, and combined words. Note any regressions or plateaus. Include details about pregnancy, birth, and early health. This information is critical for the diagnostician and is often difficult to recall on the spot.

Collect all previous medical records, developmental assessments, hearing and vision tests, speech-language evaluations, and school reports. If your child attended early intervention programs like Ontario Early Years or EarlyON, request any documentation from those programs. Organize everything chronologically.

Document specific behaviours that concern you across settings: home, school, community outings, and family gatherings. Note communication patterns, social interactions, repetitive behaviours, sensory sensitivities, and daily living skills. Use concrete examples with approximate frequency — diagnosticians find these details invaluable.

Ask your child's teachers, daycare providers, and other regular caregivers to write a brief description of your child's behaviour in their setting. Some assessment centres provide specific forms for third-party input. Different observers notice different things, and this multi-setting perspective strengthens the assessment.

Explain the assessment in age-appropriate terms. For younger children, you might say "We're going to visit someone who wants to play and talk with you." For older children, explain that the visit helps people understand how they think and learn. Visit the assessment site in advance if possible, or show photos. Plan for comfort items.

Assessments typically last 2-4 hours and may be split across multiple sessions. Ensure your child is well-rested and has eaten. Bring snacks, comfort items, and any fidgets or tools your child uses. Arrange childcare for siblings. Bring your documentation binder. Arrive early to complete intake paperwork.