Here is what we know, (or what we think we know.)  Autism is a “spectrum disorder” with a wide range of disability level.  The entire range has only recently become well-defined, and the criteria have become easier to meet as our knowledge has expanded.  Also, much more media attention and education related to the detection of the disorder have come about in recent years.

The risk of autism increases among siblings.  Genetics are definitely a factor in autism spectrum disorders, but they are not the only factor.  If one identical twin is autistic, the other does not always also have autism.  It seems likely that some combination of genetic factors and environmental triggers is responsible.  Scientists have researched possible culprits such as vaccinations as the environmental triggers, but so far, there has been no smoking gun.  Some believe that the environmental trigger may occur in the mother while she is pregnant and not after birth at all.

So, on to their study, which is a lesson in facts and fictions.  The authors compared rates of autism with rates of cable television subscriptions.  Since they did not have a way to measure actual television viewing, they added weather patterns into the mix.  Since bad weather patterns (that is, more precipitation) have been shown to be related to increased television viewing, they used them to extrapolate when and where viewing rates intensified.  Since autism rates were found to be correlated with their estimates of television viewing, they suggested that television viewing causes autism.

First of all, here’s a lesson in correlation versus causation.  They are not the same thing.  Just because two things occur together, does not mean that one caused the other.  A third variable could be causing both of them to occur simultaneously.  The articles about the study and their responses present some ideas:  Maybe cable television is more prevalent in areas with wealthier parents who can afford health insurance and who may be more relentless in getting diagnoses for their children.  Maybe factors such as mold or indoor air quality are the true cause.  (My own suggestions for possible causes include cleaning products, some food item, microwave ovens, which came about the same time as cable television, or something toxic in the rain, itself.)  It could really be just about anything and still be consistent with their findings.

Or, maybe making the disorder easier to diagnose is at least part of the explanation for more cases of autism.  The causes could even possibly be reversed.  Autism and other disabilities could lead to more television watching.

Another problem with the study is the fact that the California Department of Developmental Services states that their statistics, which were used by the economists, are not valid for scientific research.  The autism study is yet unpublished.  You have to wonder why.  Is it because of any or all of these problems?  For such a study to be taken seriously, it must be published in a peer reviewed journal.  Peer review is important; it means that the paper and the science behind it have passed scrutiny by others in the field.  Whenever there’s a debate or conflict about some research, you should always defer to whatever was peer-reviewed.  This will come up time and time again on this blog.

I will say one or two things in their defense.  They do state that some type of direct testing of actual television viewing is necessary to validate their findings.  That’s true.  I will also give them credit for trying and for generating a discussion, which could just possibly lead to the detection of the real cause, whether it’s television viewing or some other factor that just happens to occur along with television viewing.

Finally, if you are interested in learning about autism or what it’s like to be autistic, I recommend reading The Curious Incident of the Dog in the Night-Time by Mark Haddon.  It’s very interesting and even humorous, but you’ll learn something too.