Monday, May 03, 2010

Autism Disorders and Intellectual Disability: Claim that 75-80% of Persons with Autistic Disorder are Intellectually Disabled is Based on Credible Authorities

UPDATE: Alan Griswold is in very deep denial. I have now provided 3 credible sources to support the 75-80% range of persons with Autistic Disorder as also being Intellectually disabled - the ICD, the CPA and the CDC and Mr. Griswold can only repeat  his opposition to an association between Autistic Disorder and Intellectual Disability.  Of course accepting this information would require Mr. Griswold to reject his contribution to the world's discussion of autism disorders, his book Autistic Symphony which rejects autism as a medical disorder:  

"Autistic Symphony offers a unique look at the fascinating subject of autism. Challenging the psychiatric and scientific perspectives that focus exclusively on disabilities and impairments, Autistic Symphony celebrates the challenges and rewards experienced by every autistic individual, and argues that far from being a medical monster, autism is one of our culture's greatest strengths."
As I mentioned in my previous post Alan Griswold of Autistic Aphorisms is one of those comfortable with speculation that Jesus Christ may have been autistic but is not comfortable with the fact that many persons with Autistic Disorder are Intellectually Disabled.  Mr. Griswold and Astrid at at  Astrid's Journal disagree with my numerical references and wrongly describe them as self constructed.

My claim is not that 75-80% of all persons with an Autism Spectrum Disorder are also Intellectually Disabled as Astrid in particular seems to think. My assertion is that credible authorities have stated that 75-80% of persons with Autistic Disorder are intellectually disabled.  I stand by that assertion and, once again, for those who actually read before reacting, offer the sources:

1. Canadian Psychological Association    Autism Brief to the Standing Senate Committee on Social Affairs, Science and Technology November 9, 2006.

In that brief the CPA refers to 2 separate categories "Autism" and Asperger's":

"Cognitive impairment is present in about 80% of persons diagnosed with Autism and
general intellectual functioning is most often below average
. Persons diagnosed with
Asperger’s Disorder have average to above average intellectual functioning.


In sum, persons with ASD present with a wide range of impairments in cognition, language and
behaviour which present in some common but reliably distinct ways between Autism and
Asperger’s disorders

2. Center for Disease Control Counting Autism 

CDC’s most recent data show that between one in 80 and one in 240 children with an average of one in 110 have an ASD. This is a prevalence of about one percent of children. These results reflect data collected by CDC’s Autism and Developmental Disabilities Monitoring (ADDM) Network in multiple communities throughout the U.S. in 2006.

Estimates are based on health and education records from participating communities, which includes eight percent of the U.S. population of eight year olds. All children in the studies were eight years old because previous research has shown that most children with an ASD have been identified by this age for services.


Cognitive Functioning (from the pdf version)


From 37.9% (Arizona) to 63% (Alabama) (overall average: 43.8 %) of the children identified with an ASD also had an intellectual disability (an IQ ≤70, at the sites that had test results on intellectual ability for at least 75% of the children identified).


From 29.3% (Colorado) to 51.2% (South Carolina) (overall average: 41.0 %) of the children identified with an ASD also had an intellectual disability (an IQ ≤70, at the sites that had test reults on intellectual ability for at least 75% of the children identified)

The CDC figures of 41-44% for all persons on the Autism Spectrum having an intellectual disability are consistent with the 80% figure for those with Autism EXCLUDING Aspergers cited by the CPA. These figures and sources are my authorities for the upper end of the 75-80% range of persons with Autistic Disorder having an Intellectual Disability.  That is not a self constructed figure.
The lower end of the range I cite is the figure based on older sources like the 1992 ICD diagnostic criteria for Autism:
3.The ICD-10 Classification of Mental and Behavioural DisordersWorld Health Organization, Geneva, 1992

F84.0 Childhood Autism

A pervasive developmental disorder defined by the presence of abnormal and/or impaired development that is manifest before the age of 3 years, and by the characteristic type of abnormal functioning in all three areas of social interaction, communication, and restricted, repetitive behaviour. The disorder occurs in boys three to four times more often than in girls.


All levels of IQ can occur in association with autism, but there is significant mental retardation in some three-quarters of cases.

F84.1 Atypical Autism

A pervasive developmental disorder that differs from autism in terms either of age of onset or of failure to fulfil all three sets of diagnostic criteria. Thus, abnormal and/or impaired development becomes manifest for the first time only after age 3 years; and/or there are insufficient demonstrable abnormalities in one or two of the three areas of psychopathology required for the diagnosis of autism (namely, reciprocal social interactions, communication, and restrictive, stereotyped, repetitive behaviour) in spite of characteristic abnormalities in the other area(s). Atypical autism arises most often in profoundly retarded individuals whose very low level of functioning provides little scope for exhibition of the specific deviant behaviours required for the diagnosis of autism; it also occurs in individuals with a severe specific developmental disorder of receptive language. Atypical autism thus constitutes a meaningfully separate condition from autism.

* atypical childhood psychosis
* mental retardation with autistic features
These three authorities are the primary sources for my assertion that 75% (3/4 in the ICD) to 80% (CPA, CDC) of persons with Autistic Disorder also have intellectual disability.  Those are not self constructed figures as claimed by Alan and Astrid.  They are figures provided by credible authorities.


Claire said...

Keep pounding the truth home, Harold. It needs to be done.

Adrianna said...

Some people seem to be unaware that there are other ways to measure intellect without the use of standard IQ tests. The truth is that you don't need a formal test at all to see if someone is mentally retarded. If an adult, after years of rigorous instruction, cannot read beyond kindergarten level, cannot engage in any level of self-care, does not engage in any form of communication or very little communication, cannot demonstrate understanding of abstract concepts, etc. that person...I would think...would be a good candidate for an MR dx.

No one is saying that they are unteachable, just that they are more difficult to teach and many will not progress beyond a certain point. Some profoundly mentally retarded individuals are savants, but that fact that they excel at something does not take away from the reality of their impairments in other areas. Likewise, that mentally retarded autistics can learn, and that not all low-functioning autistics are retarded, does not distract from the *fact* that many low-functioning autistics are also MR and that the learning capacity of these people is very limited.

I'm at a loss as to why so many people are offended by this. No one's saying that all autistic people should be diagnosed as MR. Back pain is a common symptom of scoliosis, as is visible deformity, so they are included in the medical literature as symptoms of the disorder. Yet no one is saying that you must have back pain and visible deformity to get the diagnosis. All you need is a curvature of the spine. Including those two symptoms speeds the identification process and adds understanding to what patients are experiencing. If you didn't include those two features, on the other hand, there is a real chance that they will be treated as having originated from something else.

Long ago, it was believed that the deaf could not learn because they could not communicate. However, over the years, deaf people have developed their own sign languages and some have learned to speak. With the ability to communicate, they were able to learn just as well as anyone else. We all get that some people may be mistaken for being MR when they are not and that we should never write anyonee off.

Yet again, if an *adult,* with years of instruction, still cannot read anything more complex than Dr. Seuss, he is probably MR.

Curtis said...

Well done. I love it when bloggers verify their stats with links to Government sites. It's something the deniers can't deny!

Ian MacGregor said...

I know three boys with Down syndrome in their mid-teens. They have vastly different intellectual capabilities. The one I know best is in the middle, he is conversational, but obviously has some mental problems, his friend is the second young man. If you didn't notice his facial features, then you would not suspect him of having Downs at all. Indeed after seeing him a few times, one does not notice such things anymore. The third person is quite intellectually disabled and is unable to communicate.

However there is a completely objective test for Downs, the presence of a third copy of chromosome 21.

In autism the criteria is subjective. There are tools which metal health professionals use to perform the diagnose. These tools are in part dependent on the professionals expertise.

The three young men with Downs have different prospects for their lives, but nobody can claim that anyone of them does not have Downs.

Because of the partly subjective nature of the Autism diagnosis, this is not true of Autism.

My daughter followed the development patch of developing almost no social skills, having intellectual skills which were possibly beyond the norm, and having close to normal language development, simple phrases such as I want or "got the Q" as she sat in my lap while I played scrabble; This before her 2nd birthday. Then she regressed very much, lost all ability to communicate, no longer wanted to have books read to her. We thought she would have been reading before three. She also became pretty violent, which devastated her mother. One does not expect to be scratched and bitten when holding one's child.

Time and a lot of help and probably the judicious use of medicine over the past decade has changed her quite a bit. I love to take her hiking on the weekends. I love it when she smiles at me to show that she is enjoying herself.

Her intellectual improvement has not been near as great. Her method of communication is to bring us things. For instance if we she wants a drink, she will bring us a glass. She is not potty-trained and absolutely unaware of traffic dangers etc.

Their is a movement to deny children like my daughter an autism diagnosis. This movement says, that it does not matter how many autistic traits are displayed, her intellectual disability disqualifies her. One researcher has tried to not only exclude children with intellectual disabilities, but also those with speech impairment. Wanting to count only those children whose disabilities like in social skills.

I wonder if People don't want to believe the numbers because they don't want to accept that children like my daughter are very much autistic. They certainly don't want to accept that her intellectual problems stem from her autism. The same epigenetic process which caused severe social disabilities in their children, caused that and intellectual disabilities in mine.

On our hike last weekend we were joined by a father and his Aspergers son, his NT daughter, and two of his daughter's friends. They were all 6-8 years old. The child with Aspergers was much closer to the NT children, than to my daughter.

I have a problem of that child or an HFA child of similar skills having the same diagnosis as my daughter. This may be why I think many with high-functioning children, don't see my daughter as autistic.

I think that Autism is much too widely defined. Their is a magnitude of difference between my daughter and my friend's son. I don't see them as having the same condition, even though it is plausible the agent of their disabilities is the same.

I'd like to see different diagnoses for HFA and LFA kids. But bear in mind many kids will make the leap from LFA to HFA between about 3 and 6. So perhaps this diagnosis needs to wait until the appropriate age.

Anonymous said...

Ian, I'd also like to know the differences between HFA and LFA, there was an individual online whom claimed to have high functioning autistic disorder(not aspergers she clearly pointed out), without mental retardation or basically a average-above average iq, similiar to a person with aspergers but probably spoke late, or was more "severe" as a child.

My child has autistic disorder, cognitive impairments, and a borderline to low iq. To me he is high functioning, he can speak, can dress himself, can feed himself and is potty trained although he will need constant assistance throughout his life, will never be able to live on his own, can't navigate this world at all, but I feel since he accomplished all of what I said above, compared to my other child who cannot speak, cannot dress themselves nor anywhere near potty trained is considered high functioning.

To me autism is a social impairment, communication impairment, significant developmental delays, along with some form of cognitive impairments and/or intellectual impairments. When somebody talks of their autistic child excelling in art so amazing they can even display it themselves, the next einstien, with amazing talents, what???? That isn't autism, that has to be something entirely different. I think when they added aspergers it changed the way people looked at autism, and now like you said, Ian, people don't want to accept the severe side of autism like our children.

Both my boys have autistic disorder, both with cognitive impairments, both are different functioning levels, yet both are not genius's, with normal iq or high iq, or may be socially awkward, or have some communication deficits, no that isn't autism, that is Aspergers, not even HFA to me that is. Aspergers is an entirely different disorder, if your child has an average or above average iq, has no severe social impairments just social awkwardness, no cognitive impairments or intellectual disability, and no severe self care deficits, then it isn't autism or autistic disorder IMHO!

High functioning is somebody like rainman or my one son who although is obviously cognitively impaired and affected by "classic" autism but is able to communicate his needs one way or another, potty trained, and can control his wild behavior at times, and Low functioning is like my son who cannot even put a shirt on without assistance, can't even wipe his own butt, or use a fork or knife, where special communication devices like dynavox, or the picture exchange system are virtually impossible for him. I too would love to read the differences between low and high functioning autism, would be interesting to know!

Harold, amazing post, love your blog, your conor sounds a lot like both of my boys in some aspect! I posted a couple times before, but not recently. Like Claire said, keep pounding the truth!!!