4/11/2010

The Autism-Vaccine Link is Myth 41

*Updated: Perhaps, if a reader skims this piece rather than reading for comprehension, he might miss the title of the book: 50 Great Myths of Popular Psychology. The autism-vaccine link is the book's myth 41.*

Always in search of new and interesting material to incorporate into my psychology classes, I'm currently reading 50 Great Myths of Popular Psychology: Shattering Widespread  Misconceptions About Human Behavior (2010) by Lilienfeld, Lynn, Ruscio, and Beyerstein. It's a fascinating read and well worth your time if you're interested in seeing how many things you commonly believe to be true but that research shows to not be. It's humbling (and at times amusing) and entirely necessary as a reinforcer to how easily we can be wrong.

The autism/vaccine myth warrants attention in both the introduction and later on in the book (and facilitated communication gets its shout down in the main book, as well, as does the popular misconception that most autistics are savants). One of the ten sources of error that the authors provide an overview of is "selective perception and memory." If you've spent any time at Countering, you know that these are things I talk about a lot (I do so even more in my classes because I really, really want students to get that). Lilienfeld et al. write:

"As we've already discovered, we rarely if ever perceive reality exactly as it is. We see it through our own set of distorting lenses. These lenses are warped by our biases and expectations, which lead us to interpret the world in accord with our preexisting beliefs. Yet most of us are blissfully unaware of how these beliefs influence our perceptions" (11).

According to Lilienfeld et al., the autism/vaccine link in people's minds is a "probable example of illusory correlation" (13). Illusory correlation is "the mistaken perception that two statistically unrelated events are actually related" (12). Later in the book, when they cover the autism-vaccine myth, the authors note that even the "autism epidemic may be an illusion" (198).

It's a frequent refrain here that there is a widening disparity between what researchers know and what the general pubic knows. This is undeniable. The media does a piss-poor job of disseminating scientific information to the public, in general, due in part to inadequate understanding by their writers and by the need for tasty sound bites and controversy.

As a college instructor in two separate fields, with the distinct advantage of getting a wide diversity of students, since I teach developmental reading and writing in addition to freshman composition and psychology courses, it becomes increasingly apparent that, at least from my sample pool, critical thinking skills are poorly taught at the secondary levels. Questioning mainstream claims regarding a whole host of topics is not something generally done. I can't tell you the number of people who believe we only use ten percent of our brains.

We've got to take responsibility for our own educations; we've got to question common conceptions and extraordinary claims. And where we can, when we realize we've fallen to one of the common errors we all make, we ought to face up to them, painful as that might be, and own them.

Here are, according to Lilienfeld et al., the ten common errors we make, with some brief discussion from me:

1. "Word-of-Mouth" -- Hearing  a claim over and over doesn't make it true, but we will believe it if we hear it enough and don't do the hard work of evaluating it. It is one of the reasons why I consider  the anti-vaccine movement so dangerous.

2. "Desire for Easy Answers and Quick Fixes" -- You need go no further than your local infomercials, Mercola's woofested site, or AoA's sponsors.

3. "Selective Perception and Memory" -- We see what we want to see and distort our memories to match.

4. "Inferring Causation from Correlation"

5. " Post Hoc, Ergo Propter Hoc Reasoning" -- "A precedes B, then A must cause B" -- again vaccines, autism.

6. "Exposure to a Biased Sample" -- See AoA  or lots of folks who conceive of autism as being only what they've seen, or the tendency to lump all medical issues in with autism and call gastro issues autism (which also comes into play in errors 4 and 5).

7. "Reasoning by Representativeness"  -- Just because there may be superficial similarities, doesn't mean there are deep ones. Think about when you've dated a guy, it doesn't work out well, and you meet a new guy who looks like the old one and you think that guy will be like the first. Or the whole misguided mercury poisoning and autism symptoms are identical.'

8. "Misleading Film and Media Portrayals" -- Ummm, Parenthood anyone? How about Rain Man? (the book's authors use Rain Man).

9. "Exaggeration of a Kernel of Truth" -- The authors give the 10% myth. None of us maxilly use our brains, so out of this grew the 10%.

10. "Terminological Confusion" -- I've written about the need to operationalize definitions so we know how we're defining something; the misuse of terminology by the public causes serious miscommunication issues between the scientific community and the public and among community members.

5 comments:

Autism Reality NB said...

I am so glad that KWombles has declared any vaccine autism link to be a myth. Someone will have to tell Dr. Bernadine Healy former NIH director who said that the epidemiological studies allegedly disproving any thimerosal autism connections are not specific enough to rule out the impact of thimerosal on vulnerable population subgroups.

Or they could tell Dr. Jon Poling, academic and clinical neurologist, father of a successful vaccine court litigant and (when government setttles its because they have bad case)who has stated in an op ed piece in the Atlanta Constitution that more research is needed on that issue.

Perhaps they should also let Dr. Irva Hertz-Picciotto, Ph.D., Professor, UC Davis Mind Institute,and Chief, Environmental and Occupational Health at UC Davis, an internationally renowned environmental epidemiologist who has published widely on environmental exposures, including metals, pesticides, air contaminants and persistent pollutants like PCBs, their interactions with nutrition, and their effects on pregnancy, the newborn, and early child development.

Dr.Dr. Irva Hertz-Picciotto wrote just this week that:

"the studies of thimerosal have been noted to have methodologic problems that would have reduced the ability of these studies to validly test the theory, underscoring the need for stronger science on this question."

Dr. Irva Hertz-Picciotto recent comments can be found at:

http://www.scientificblogging.com/environmental_epidemiology/environmental_factors_contributing_autism

Dr. Irva Hertz-Picciotto's resume, should you decide to go Orac on us and mock her opinions with a personal slam can be found at:

http://www.scientificblogging.com/profile/irva_hertzpicciotto

The issue of thimerosal and its possible role in causing or contributing to autism is not proven OR disproven. It is a live issue not a myth.

KWombles said...

Harold, do you go off half-cocked all the time? Or just with me? :-)

Lilienfeld et al (2010) declared the autism-vaccine link to be a myth, not me.

The IOM (2004) declared there was no evidence for a link between autism and vaccines.

You offer individual's opinions not based on the research at hand.

But now that I know that Poling and Picciotto (especially since you called Picciotto Dr.Dr.) have spoken, I'll of course ignore the consensus of the scientific community. Thank you so much for bringing that to my attention. I mean, Poling absolutely has all the scientific evidence in the world backing him. Thanks! You're so thoughtful!

In the scientific community, the thimerosal issue is not an open one, Piccioto notwithstanding. Keep hanging with the AoAers and before long we'll see you rewriting your history to blame your son's autism on thimerosal.

David said...

I think "illusory correlation" is an overly harsh phrase for the given meaning. If two events REALLY occur at the same time, then they can be said to correlate whether there is a causal relationship or not. I would consider "illusory correlation" warranted where there is not only no causal relationship, but even the perceived correlation in time is a relic of selective perception or even false memory. I think it is increasingly clear this is what happened with Jenny McCarthy.

KWombles said...

Holy crap, Harold, is there some reason you lifted without quotes the information on Hertz-Picciotto without attributing it? I mean, come on! At least you quoted her actual words, but you really should have put quotes around her bio, too, you know. And you do know. Tsk.


http://www.scientificblogging.com/profile/irva_hertzpicciotto

"Irva Hertz-Picciotto, Ph.D., Professor, UC Davis M.I.N.D. (Medical Investigations of Neurodevelopmental Disorders) Institute and Chief, Environmental and Occupational Health at UC Davis, is an internationally renowned environmental epidemiologist who has published widely on environmental exposures, including metals, pesticides, air contaminants and persistent pollutants like PCBs, their interactions with nutrition, and their effects on pregnancy, the newborn, and early child development."

KWombles said...

Oh and you left out the key part of the sentence you did quote:

"Much attention has focused on vaccines as potential causes of autism. Several different hypotheses have been proposed. No rigorous study has demonstrated a link either with the MMR vaccine or with vaccines containing the preservative thimerosal."

There you go. She also doesn't state what the problems were with the studies, which weakens the assertion and what you are trying to use it for. And no study is perfect and flawless. That's why replication and refinement are key.

It still renders your allegation that the question is an open one within the scientific community inaccurate.