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IQ Testing

Autism and I.Q. Tests:

How To Get a Valid IQ Score for a Child With Autism

By Gary J. Heffner, MA

As with most articles on this site, this page started with a question from a parent: "My child was just tested and they say he has autism and mental retardation. Is he mentally retarded?" To me the added diagnosis is the equivalent of kicking someone when they're already down on the ground. Let me try to answer this question.

I used to assess the intelligence of children and adults when I worked as a behavior specialist for the Army, a private center for persons with developmental disabilities, a state mental health program, and a state hospital. Here's what I know about IQ testing - A valid IQ score requires at least three things: social interaction, some form of communication, and general behavior control.

The child or adult is required to interact with another person, often a stranger - this is extremely difficult for persons with autism (in fact, it is a criteria for their diagnosis). So you can say they have one strike against them coming into the IQ test situation. The second thing needed for a valid IQ score is some form of communication - persons with autism, by diagnosis, have qualitatively impaired comunication abilities. Most IQ tests are heavily weighted with verbal abilities or at least partially rely on these skills for a good total IQ score. The examiner asks a question and the person is expected to respond - this is strike two for most persons with autism. Finally, an IQ score depends upon at least a minimum of behavioral cooperation between the examiner and the subject. Unfortunately, many children and adults with autism are not inclined to cooperate. Part of their diagnosis is that they have "repetitive and stereotyped patterns of behavior, interests, and activities", which are often at odds with what the examiner has in mind (there are very few hand-flapping tasks on IQ tests). It takes just a few runs around the room, a few stubborn refusals, or a few thrown test materials to prompt the examiner to write "untestable" on his IQ test forms. Can you say, "Strike three?"

The bottom line is: It is extremely difficult to measure the IQ of a person with autism. Their disability (social interaction problems, communication delay, and behavioral issues) all work against an accurate measure of their intellectual abilities. Although I do not recommend ignoring IQ test results, I would recommend paying little attention to low IQ scores for children with autism. In addition, make sure you do not limit the activities you present to a child with autism just beacause his IQ score may be low. This includes educational placement and opportunities. Typically, children with autism have splinter skills that may be at or above the average level of intelligence. Although adults may also show splinter skills and their IQ scores are also affected by the above three variables, their IQ scores are usually more accurate or at least less changeable by behavioral intervention.

So how can you get a good IQ score for a child with autism?

1. Choose your examiner well. Preferably he or she will know autism and how to work effectively with persons with autism. Ask other parents of children with autism about who they used to assess their child. Also, does your child respond better to males or females? Choose accordingly.

2. Make sure the child is not ill, is not in a bad mood, having a bad week, and is at his or her best physically and emotionally. It would be better to reschedule the testing than to have the examiner add these words to a low-scoring IQ test: "Subject was not at his best today, according to the parent." You know your child better than anyone and can tell the examiner what part of the day would be ideal for testing, etc. - use this knowledge to your child's advantage.

3. Talk to the examiner before the testing and tell him or her all about your child: what he likes, doesn't like, what reinforcers to use, what to say and what not to say, and all the little things that would make the testing situation as ideal as possible. You may have to explain to the examiner how your child's autism presents itself. If your child is nonverbal discuss alternate ways he or she communicates. Explain any sensory issues your child may have and what can be done to help. 

4. Take your child to the testing site ahead of time to get him or her used to the setting. Write a social story about IQ tests that explains the reasons for testing, what will happen, and (more importantly for the child) what wonderful thing you will give him right after he does his best on the IQ test (McDonald's is my choice). Read the social story to your child to prepare him or her for the test. Try to get the examiner to spend some non-threatening time with your child ahead of time - that way he or she will not be a complete stranger.

5. Discuss the tests the examiner plans to use. Whether your child is verbal or not, a non-verbal intelligence test is a good idea for children with autism (e.g., Test of Nonverbal Intelligence, Third Edition or the Leiter International Performance Scale - Revised). Studies have shown that such tests compare favorably with the performance IQ scores on typical IQ tests but not the verbal IQ scores. Typically, children with autism have higher performance IQ scores than verbal IQ scores. Children with autism usually have better receptive language abilities than expressive language abilities - discuss this with the examiner as well. Another focus for testing is adaptive skills. Usually, the Vineland Adaptive Behavior Scales are used to assess self-help and other adaptive skills. Request that the examiner uses the Vineland Supplemental Norms for Persons with Autism. Note: Many examiners do not take too kindly to being told how to test a child and what tests to use - be careful, respectful, and assure the examiner that you will trust his or her judgment and that these are merely recommendations.

6. For me the preferable diagnosis (regarding mental retardation) with all children with autism or PDD-NOS is "deferred". Studies show that IQ scores, which are supposed to be fairly stable over the course of a child's life, can increase dramatically when applied behavior analysis (ABA) is used to improve the child's communication and behavior. This tells me that IQ scores for children with autism (and especially diagnoses based upon those scores) should be viewed with great caution by all concerned. Discuss this preference with the examiner, if he or she has not already thrown you out.

7. Finally, pray. The Lord knows autism and He knows how to help us navigate through all these troubled waters of education and life.

Many children with autism will also be diagnosed with mental retardation at some point in their lives. Those of us who have worked with both populations know that, while there may be some similarities in the two groups, there are far more differences. Usually, people with autism and legitimate mental retardation are considered "low-functioning autistics". Before the label is placed on your child, make sure it aptly applies. Unfortunately, many people that would not give up on a child with autism may do so on a child with both diagnoses. If the child has both diagnoses legitimately, that's okay, the child can still learn and will still benefit from ABA and other services.


Here are some additional links that may help:

~GJH~April 2005~

DISCLAIMER: This site is intended to provide basic information resources on Autistic Disorder. It is not intended to, nor does it, constitute medical or other advice. The author of the web site is not a medical doctor. Readers are warned not to take any action with regard to medical treatment or otherwise based on the information on this web site or links without first consulting a physician. This web site does not necessarily endorse any of the information obtained from any of the links on this page or links that other pages may lead you to. Neither does this web site promote or recommend any treatment, therapy, institution or health care plan. The information contained in this site is intended to be for your general education and information only and not for use in pursuing any treatment or course of action. Ultimately, the course of action in treating a given patient must be individualized after a thorough discussion with the patient's physician(s) and family.

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