Intelligence Tests for Autistic Children

Most of the time, child psychologists and other professionals rely on the same IQ tests to measure the intelligence of all children. Many autistic children have test results that suggest low intelligence on the basis of these standard IQ tests.

Yet recent findings (and new tests) suggest that typical intelligence tests, based on information collected from neurotypical children, are inappropriate for autistic kids. This means that autistic children may receive inappropriate results, and the IQ tests themselves may even be administered improperly.

This article explains what IQ tests do, and why they have limitations. It can help you to better understand the kinds of intelligence tests your autistic child can or should take.

Young Boy Playing the Blocks
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Should IQ Tests Be Administered to Autistic Kids?

Typical IQ tests are built around the assumption that test-takers can understand and use spoken language at an age-appropriate level. Many autistic kids, however, don't demonstrate age-appropriate communication skills. This means that they start at a disadvantage.

In addition, autistic children may react badly to a new situation and an unknown tester. Even the physical conditions under which they're asked to take the test (usually a room with bright fluorescent lights) can create challenges.

It's important to note that some research also suggests that autistic children are simply less motivated to take or do well on an IQ test because they are less concerned with or aware of others' judgments and expectations. Providing additional non-social motivators, such as small prizes for compliance, can make a big difference in test outcomes.

According to James Coplan, MD, a developmental pediatrician and researcher specializing in autism, intelligence tests for autistic children should be administered by someone who is comfortable and experienced working with neurodivergent children.

How Do Professionals Measure Nonverbal Intelligence?

Young autistic children are often nonverbal or have significant issues with processing language and responding verbally. Dr. Coplan notes that verbal responses may not be a good measure of IQ, nor a child's ability to manage interpersonal relationships, sensory input or motor skills. In fact, he says, "Nonverbal intelligence is the single biggest factor influencing the outcome."

How do you measure nonverbal intelligence? Dr. Coplan recommends the comprehensive Test of Non-Verbal Intelligence (TONI), saying that children who do poorly on typical intelligence tests may do very well on the TONI. The test looks more directly at what children know than other tests—not at how well children can use language to communicate what they know.

What's more, the test is administered nonverbally. By around one year, a child should be able to show that he knows an object still exists, even when it's out of sight. Games, such as peek-a-boo, become meaningful at this point.

At 12 to 14 months, says Dr. Coplan, a child should be able to use objects as tools, solve simple problems and show an interest in cause and effect. Autistic children, however, may do all of these things idiosyncratically. For example, Coplan describes one parent as saying, "My child uses my hands as if they were surgical instruments." By age 2, children should be combining different things together to see what they do. Stacking and dumping are signs of this type of development. "Typical children will use language," says Dr. Coplan, "but adaptive skills (fasteners, clothes on and off, etc.) are all nonverbal problem-solving skills you find at 36 months."

Other tests for intelligence measure fewer aspects of intelligence but may also be useful. The Raven Matrices measures a child's ability to identify patterns and reproduce information. The Bender Gestalt tests involve copying pictures (and require physical output). Depending upon the child, these and other additional tests may be helpful in determining the best treatment plan.

7 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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Additional Reading
Lisa Jo Rudy

By Lisa Jo Rudy
Lisa Jo Rudy, MDiv, is a writer, advocate, author, and consultant specializing in the field of autism.