Autism Increasing

Prevalence of Autism Growing. Autism is about 10 times more prevalent today than it was in the 1980's, according to the largest U.S. study ever on the problem. By Sandra Blakeslee. [New York Times: Health]

This is an interesting problem, but the author of the NYT article glosses over the important point.   As the definition of "autism" has expanded, comparing the prevalence of this disorder over time is impossible to do accurately. 

The next question, of course, is why is autism increasing (if in fact it is)

20 years ago in college (ouch .. am I that old?) I read How To Lie With Statistics.  It's an easy read.  Here goes ..

Autism has increased tenfold since 1980

Get it?  So what.

Of course, the MMR vaccine will come up in this discussion, but there's now ample research that there is no clear connection.  This is statistics 101.  Tick and Tock are likely to be perfectly correlated, but no one would suggest that Tick causes Tock.  Nor does organic farming cause autism, despite the correlation.