Special needs

How Accurate are Online Autism Tests?

Author, Autism mom and Chair of Kerry’s Place Autism Services, Jan Stewart shares what you need to know

How Accurate are Online Autism Tests?


A few weeks ago, a mother of a two-year-old reached out to me. She was concerned that her son didn’t seem to understand what other children his age understood, and often didn’t look at her when she talked to him.

Another parent called me about her younger child. Her nine-year-old was non-verbal, didn’t like loud sounds or bright lights, and had been diagnosed with autism. Her four-year-old seemed to be engaging in many of the same behaviours — although he chatted up a storm and was outgoing. She didn’t know if he was imitating his older brother or was also autistic.

These parents turned to online tests to determine if their children might be autistic. If you're considering using one of the available online autism tests, there are a few things you need to keep in mind.

How accurate are online autism tests?

Online tests are increasingly popular and can be alluring, quick, easy to understand, and complete. But they are not diagnostic tests.

These tests can act as a good starting point. They are most helpful in identifying if a child has autistic traits and characteristics to determine whether further evaluation is needed. Remember that traits and characteristics do not necessarily mean a child is autistic.

Autism diagnosis entails professional clinical judgment. “We are not yet at the point where an autism diagnosis can occur without a clinician,” says Dr. Melanie Penner, Senior Clinical Scientist and developmental pediatrician at Holland Bloorview Kids Rehabilitation Hospital.

There can be a myriad of reasons that a child has social or communication difficulties. Online tests do not consider important external/environmental risk factors such as extreme prematurity, low birth weight, birth difficulties, or having an autistic sibling.


These can only be identified through an understanding of physical, psychological, emotional, social, and developmental factors by a healthcare provider observing the child’s interactions and behaviours.

Dr. Evdokia Anagnostou, Vice President of Research and child neurologist at Holland Bloorview, notes that these tests have a high rate of false positives. “Results can be inaccurate and misleading. The key point is to understand the needs of each child.”

mom sitting at a desk with a computer getting a hug from her son Getty

What are some of the most popular online tests for autism?

Not all online tests are equal. Some have been researched more thoroughly and with more significant input from experts than others.

One of the most widely used online screening tools is M-CHAT-R/F, the Modified Checklist for Autism in Toddlers, Revised. It’s free, takes about 10 minutes and asks 20 yes/no questions about a child’s behaviour from ages 16-30 months. These questions include, for example:

  • When you smile at your child, do they smile back at you?
  • If you point at something across the room, does your child look at it?
  • Is your child interested in other children?
  • Does your child respond when you call their name?
  • Does your child play pretend or make-believe?

Results are immediate and rank behaviour on a scale from zero to two (low risk), three to seven (moderate/medium risk) and eight  to 20 (high risk).


There are a myriad of additional online tests for autism. For example:

  • Survey of Well-Being of Young Children (SWYC): for parents/caregivers of children under five years of age, takes about 15 minutes to complete with 33-40 questions around developmental, emotional/behavioural and family factors;
  • Repetitive Behaviour Questionnaire (RBQ): 33 questions that focus on repetitive behaviours, such as arranging toys in rows or patterns, whether a child touches parts of their body or clothing repeatedly and whether they rock back and forth or side to side. There are different RBQ questionnaires depending on the age of the child;
  • Childhood Autism Spectrum Test (CAST): for parents/caregivers of children four to 11 years old, takes about 20 minutes to complete with 39 yes/no questions;
  • ASDetect: for parents/caregivers of children 11-30 months, it takes 20 to 30 minutes to complete with approximately 15 multiple-choice questions. The app has short videos of both autistic and non-autistic children, for example depicting a child with no or little eye contact.

Remember that online tests do not diagnose autism, and results indicating “high risk” or “high likelihood” do not necessarily mean your child is autistic. Therefore, these tests should never substitute for an actual diagnostic assessment.

As for the concerned parent of the two-year-old? After making an appointment with her healthcare provider who performed a comprehensive assessment, it turned out that her son was not autistic but had difficulty hearing. And the other parent’s suspicions were confirmed by their doctor: both of her children are autistic.

So many factors go into diagnostic assessments. First, trust your gut as a parent if you have concerns. If you wish, start with an online autism test. But don’t rely on its results to confirm whether your child is autistic. Follow up with a trusted healthcare provider. You and your child deserves nothing less.

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