In case anyone needs a reminder: vaccines do not cause autism.
The final two groups that were studied consisted of 256 children with ASD [autism spectrum disorders] and 752 matched controls. One very interesting aspect that looks as though it were almost certainly placed into the experimental design based on concerns of anti-vaccine advocates like Sallie Bernard is a group of children who underwent regression. Basically, the study examined whether there was a correlation between ASD and TCV [thimerosal-containing vaccines, i.e. mercury-containing vaccines] exposure. It also examined two subsets of ASD, autistic disorder (AD) and ASD with regression, looking for any indication whether TCVs were associated with any of them. Regression was defined as: "the subset of case-children with ASD who reported loss of previously acquired language skills after acquisition."
(via Kottke)So what did the investigators find? I think you probably know the answer to that question. They found nothing. Nada. Zip. There wasn't even a hint of a correlation between TCV exposure and either ASD, AD, or ASD with regression: "There were no findings of increased risk for any of the 3 ASD outcomes. The adjusted odds ratios (95% confidence intervals) for ASD associated with a 2-SD increase in ethylmercury exposure were 1.12 (0.83-1.51) for prenatal exposure, 0.88 (0.62-1.26) for exposure from birth to 1 month, 0.60 (0.36-0.99) for exposure from birth to 7 months, and 0.60 (0.32- 0.97) for exposure from birth to 20 months."