Tuesday, May 17, 2011

Dr. Offit on the Definition of Autism

In a recent Medscape article, Dr Paul Offit is quoted as putting forth the following idea on autism -
Dr. Offit said the study authors reach erroneous conclusions due to an erroneous definition of autism. A child with measles encephalopathy, he said, may have severe cognitive deficits that fall into the autism spectrum, but such symptoms themselves do not necessarily translate into a diagnosis of autism. 
The good doctor is of course talking about the recent paper that purports to show that autism might be more common in children compensated by the the so-called vaccine court than in the general population.  While I don't yet have much of an opinion on the paper, I do know that Dr. Offit's statement is just plain wrong.

First and foremost, a diagnosis of autism is based solely on the presence or absence of behaviors.  If you have enough of the behaviors of autism then you have autism, if you don't then you don't.  There is absolutely nothing in the definition that says anything about the underlying causes of the behaviors.  It is factually inaccurate to say that "severe cognitive deficits that fall into the autism spectrum" aren't autism.  Autism is autism - regardless of the cause.

Second, the authors in the paper actually used a validated autism screening test called the Social Communication Questionnaire (SCQ) with twenty-two of the children that they found.  While the test cannot definitively show that a person has a diagnosis of autism, it is certainly not an "erroneous definition of autism".  As a matter of fact, there are a quite a few research studies that have used the SCQ to help identify cases of autism

The problem is that Dr Offit has painted himself into a corner in regards to autism and vaccines.  He regularly says things such as "This hypothesis has been tested thoroughly. The question has been asked and answered.", as he did in this story.  He has written several books on the subject, all of which basically say the same thing - no relation between autism and vaccines.

I don't think he is now able to admit, either to himself or publicly, that he might have been wrong.  Instead he has to come up with non-autistic forms of autism and spends his time "defending" his idea against anyone who questions it.

This is precisely the reason why there is no such thing as an "asked and answered" question in science.  Once you have decided that you already have the answer you stop listening to what everybody else is saying.

6 comments:

  1. Interesting analysis. I had never heard that before.

    >>>>>This is precisely the reason why there is no such thing as an "asked and answered" question in science. Once you have decided that you already have the answer you stop listening to what everybody else is saying.<<<<<

    I guess once you have all the answers, you are a religion, not a science.

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  2. Hehe. Curious that he has no skepticism that an astronomically high 1 in 38 Korean children land on the spectrum, but Hannah Poling does not.

    The tragic part is that the very real problems of falling herd immunity will eventually be the result of this doublethink madness. The longer and more strenous the denails, the more credibility will be lost.

    - pD

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  3. Yeah, I really don't get that. How can you be a skeptic on one hand and on the other accept the astronomical 1 in 38 figure for children born in the 90s without so much as a question.

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  4. Hi MJ, hace mucho que no hablamos!

    I hope your doing well. You too pD!

    Slightly off-topic, but speaking of skepticism, what do you guys think about the interpretation (AoA and Huffpo) that Dr. Offit has made some sort of point *about vaccines* with his quoted statement? I read it as "Measles Encephalopathy" and not "Measles Vaccine Encephalopathy". I know that's not the point of this post, but I'm curious about your opinion there.

    "First and foremost, a diagnosis of autism is based solely on the presence or absence of behaviors. If you have enough of the behaviors of autism then you have autism, if you don't then you don't."

    I think Dr. Offit would absolutely agree.

    "There is absolutely nothing in the definition that says anything about the underlying causes of the behaviors."

    I think he would agree 100% here as well.

    "It is factually inaccurate to say that "severe cognitive deficits that fall into the autism spectrum" aren't autism."

    I think this is where he would disagree. I can see how that at least one or more of the 7 children with measles encephalopathy in the study link below could have presented with impaired speech/language development without a single item from the restricted repetitive and stereotyped patterns of behavior, interests and activities list. It would also seem possible that measles encephalopathy could occur in a three year-old, which by today's definition, would definitely not be autism.

    http://www.ncbi.nlm.nih.gov/pubmed/7581755

    "Autism is autism - regardless of the cause."

    Only if all the criteria are met, and the onset is prior to age 3, and Rett's or CDD can be excluded.

    I think that's exactly Dr. Offit's point. Symptoms that might meet one criteria-aspect of the diagnosis, do not automatically mean that *all* the criteria are met. He's not necessarily eloquently pointed out their use of the composition fallacy.

    An autism diagnosis includes a cognitive deficit (see speech delay). Those kids have a speech delay, therefore those kids all have an autism diagnosis.

    If you're suggesting his statement is grounded in the etiology, I'd say that looks an awful lot like a straw man.

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  5. but such symptoms themselves do not necessarily translate into a diagnosis of autism.

    Oh, come on...everybody and their dog are getting a label of autism. The umbrella is so large that kids who might have been diagnosed dyslexic are now autistic. Like my son.

    Strawman, fallacy. Those words are used like salt at every skeptic's argument buffet. To me, it's a clue someone is not using their own brain. I'm sorry to say that, Do'c.

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  6. Hi D'oC,

    "Slightly off-topic, but speaking of skepticism, what do you guys think about the interpretation (AoA and Huffpo) that Dr. Offit has made some sort of point *about vaccines* with his quoted statement?"

    He may not have intended to make a point about vaccines but given the context that his quote is in I don't think it would be stretch to extend his views to vaccine damage in general.

    His entire idea here seems to be that other things that mimic autism aren't necessarily autism if we know what the cause is. So I don't see why he would say that "Measles Encephalopathy" could look like autism but other forms of encephalopathy would not.

    "I can see how that at least one or more of the 7 children with measles encephalopathy in the study link below could have presented with impaired speech/language development without a single item from the restricted repetitive and stereotyped patterns of behavior, interests and activities list."

    Theorizing about the presence or absence of behaviors from a case study about complications arising from measles infections is a little pointless. I don't see anything in the abstract that would directly support even the idea of a speech/language delay.

    "Only if all the criteria are met, and the onset is prior to age 3, and Rett's or CDD can be excluded. "

    Only if any of the criteria for any of the pdd conditions are met - including Rett's or CDD. All five conditions are typically considered part of the autism spectrum, although Rett's and CDD are rare enough that they could be safely ignored.

    And if you look closely at the description for pdd-nos you would see that it doesn't have to appear before the age of three (CDD doesn't either). Nor does a child with pdd-nos have to have clinically significant (or severe) delays in all three areas. From the DSM IV TR -

    "This category should be used when there is a severe and pervasive impairment in the development of reciprocal social interaction or verbal and nonverbal communication skills, or when stereotyped behavior, interests, and activities are present, but the criteria are not met for a specific Pervasive Developmental Disorder, Schizophrenia, Schizotypal Personality Disorder, or Avoidant Personality Disorder. For example, this category includes atypical autism --- presentations that do not meet the criteria for Autistic Disorder because of late age of onset, atypical symptomatology, or subthreshold symptomatology, or all of these."

    Severe Social + Severe Communication or Severe Social + Severe RRBs are enough to get a pdd-nos label. Although in practice I think that most children with pdd-nos do have some level of impairment in all three area.

    "Symptoms that might meet one criteria-aspect of the diagnosis, do not automatically mean that *all* the criteria are met. "

    The choice of the phrase "fall into the autism spectrum" seems to suggest that symptoms from all domains are there. If Dr Offit had meant only communication or social problems then I would have to wonder why he would have said "autism spectrum". Especially in light of the fact that his comment was about someone else getting the definition of autism wrong.

    I suppose he might have just misspoken or was misquoted but I really think his point was that autism isn't autism if it is caused by something known.

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