The New York Times has joined those who assert that rising autism rates reflect a real increase in autism and are not explained solely by changes in autism diagnosis definitions and increased awareness:
"In the United States, anti-vaccine groups have advanced other theories since then to explain why they think vaccines cause autism. For years, they blamed thimerosal, a vaccine preservative containing mercury. Because of concerns over the preservative, vaccine makers in 2001 largely eliminated thimerosal from routinely administered childhood vaccines.
But this change has had no apparent impact on childhood autism rates. "
The New York Times argument ,previously advanced by Dr. Eric Fombonne and Dr. Nancy Minshew, only makes sense if it is based on real increases in autism rates. Increases in autism rates after removal of thimerosal from vaccines solely because of diagnostic definition changes and ascertainment factors would not indicate whether thimerosal did or did not play a role in causing autism.