Undisclosed industry funding, unsubstantiated conclusions on vaccines, and study sample alteration undermine credibility on controversial topic

A recent press release from the University of Missouri announced the results of a study on autism and Rh immune globulin (RhIg) injections, some of which contained a mercury preservative called thimerosal. SafeMinds reviewed information about this study and found several troublesome aspects, including undisclosed industry funding, unsubstantiated conclusions on vaccines and mercury, and deviation from acceptable scientific practice.

The study was funded by Johnson & Johnson, the largest manufacturer of RhIg products and the defendant in several lawsuits alleging a link between autism and mercury in RhIg. In an earlier 2005 poster presentation, the study authors acknowledged that the research was "supported by Johnson & Johnson Pharmaceutical Research," but the University of Missouri press release omits mention of this conflict of interest.
The press release headline falsely claims that the "Study Finds No Link Between Autism and Thimerosal in Vaccines." The study is about Rh immune globulin, and immune globulins are not vaccines. "The headline deceives the
public," noted Mark Blaxill, director of SafeMinds. "It says an
autism-mercury in vaccines link has been disproved when the research did not do so." In fact, the study failed to differentiate between mothers who received RhIg brands with mercury and those receiving the brand without
mercury, rendering assessment of mercury's role in autism from RhIg indeterminate.
Changes to the research sample were made in the middle of the study. The 2005 sample contained 47 mothers with more than one child with autism, while the final 2007 study only had 16 mothers with more than one child with autism. The elimination of 31 "multiplex" families means that the original sample was altered, and not just added to, after initial results were obtained in contradiction of standard research practice meant to prevent manipulation of findings.
"An earlier analysis by SafeMinds of the poster presentation revealed numerous flaws in methods, analysis and interpretation," stated Mr. Blaxill. "We are concerned many of these flaws have not been corrected and quite possibly have been amplified in the published paper. While the poster results demonstrated an increased risk of autism in thimerosal-exposed children, the written interpretation of the data claimed the opposite."
Once SafeMinds has the opportunity to review the full paper, a full assessment will be completed. SafeMinds calls for unbiased studies on the potential link between autism and mercury exposures. More information on this study is available [here].