What is the IQ of a child with autism?

Answer 1

People with autism can have any IQ, including being profoundly gifted (180+). Mental retardation is significantly more common among people with autism, but one sort of autism--Asperger Syndrome--is only diagnosed in people with normal or higher IQs.

Answer 2

One of the criteria for autism is delayed language development and delayed cognitive development, which often implies below average IQ. If a person has an IQ under 70, it is typically labeled as autism. If a person has average or above average IQ, it is typically labeled as Asperger's Syndrome.

However, if the person has traits more strongly associated with autism than with Asperger's Syndrome as an infant or toddler, he or she will often be diagnosed with autism before realizing that his or her IQ is average or above average, and then will be relabeled as having Asperger's Syndrome, pervasive developmental disorder not otherwise specified, or high-functioning autism in later years. There are proposed differences between Asperger's Syndrome and high-functioning autism, so people with autism might have IQs ranging from below average to above average, but more research needs to be done to determine if there is a distinction between the two.

In addition, there are a number of people with autism who perform well in school but not well on IQ tests, so the IQ test might not be an accurate test of IQ for some people with autism. Some have below average IQs, but earn straight-As in school.

So, at present, the average IQ of people with autism is probably assumed to be below 70, but that belief is being challenged.

Answer 3

In order to qualify for an Asperger's diagnosis, the individual must have an IQ in the Normal Range (of IQ scores) or higher. The Normal Range is where the IQ's of more than 60% of the overall population (whether Asperger/Autistic or not) lay, and is defined as being a score between 90 and 109. The lower of these two figures is of note, because it is significantly above the cut-off for an Intellectual Disability (formerly known as Mental Retardation). There is a common misconception that an individual with Asperger's is merely an Autistic who does not have an Intellectual Disability - defined as having an IQ of below 70. But any individual with an IQ between 70 and 89, having a score below the normal range, would still not meet one of the core criteria for an Asperger's diagnosis. It should also be noted that for even those with Classic (low-functioning) Autism, an Intellectual Disability features in only 50 - 70% of cases*.

As explained above, the minimum IQ for an individual with Asperger's is a score of 90. It is also of note that there is no maximum IQ score for these individuals. Scores of over 130 (qualification to Mensa), even over 200, while uncommon, occur at a somewhat higher frequency than in the general population. This is one reason Asperger's has been described by some as "Genius Syndrome". Though while this may seem the case for certain individuals, it can hardly be generalized across the entire group.

Calculating the IQ with precision for an individual with Asperger's is [often] notoriously difficult. Unlike individuals without Asperger's, who typically have a fairly even profile of abilities, a person with Asperger's may vary markedly between what they do well and what they do not. Since IQ tests were never designed for people with such fluctuations, the score for a person with Asperger's is often given as a range (e.g. 139 - 145) than as an exact figure. Two points are of note here. Firstly; because there score can be so difficult to calculate, the score is often given as being several point below what their true score actually is. The second point is that while their proficiencies and deficiencies may vary to a much greater degree than someone without Asperger's, they still manage to attain (on average) a average score several points above. This is to say that while their performance on some portions of the test are considerably below a non-Asperger with identical IQ, the areas in which they excel may be markedly superior.

NB. The IQ scores listed here are from the Weschler Adult Intelligence Scale (WAIS).

* Low-functioning does not mean low IQ, as many Low-functioning individuals have IQ scores in the normal range, and some possibly as high as 130 (98th percentile). Levels of global functioning are a person's ability to cope with the stresses of life, to feed, wash and maintain themselves (etc), and whether they can do this without the care of others i.e. parent/carer. All individuals with Asperger's, by diagnostic criteria, are High-functioning. Meaning these individuals can look after themselves without the assistence of others. Whereas Low-functioning individuals, to varying degrees, cannot. All so-called "normal people" are High-functioning. IQ has only a partial relationship to global functioning. In order to be considered High-fuctioning, the individual cannot have an Intellectual Disability. Whereas Low-functioning status is independent of IQ. These individuals may or may not have an intellectual disability.