Several years ago, at the invitation of a journal editor interested in the issue of industry corruption of scientific journals, I drafted an article on the Denmark epidemiology studies. I had just published a couple of articles on autism in other journals and was interested in making additional contributions. I was outraged that the sponsorship of the Danish publications had been spearheaded by the company that manufactured the thimerosal-containing vaccines investigated for their connection to autism and astonished that this connection had received no attention whatsoever. I did a simple analysis of the social network of authorship to show that a single collaboration was behind the entire publication program, wrote up the results and sent a first draft back to the journal.
The peer reviews that came back were constructive and helpful, but also argued for some pretty extensive revisions. The changes had little to do with the conflict of interest argument and mostly involved relatively arcane issues of network analysis and asked me to explain some of the technical choices I had made and how the results of these technical choices should be interpreted. When I got the feedback, I was quite busy on other projects and had begun losing my enthusiasm for running the publication gauntlet at academic journals. As a result, I gave up on the effort and never responded to the suggestions.
As the scandal involving Poul Thorsen’s misrepresentation of his employment and possible misappropriation of funds, it seemed to me that this analysis took on new relevance. So we have decided to run my original draft here in its entirety. We hope that you’ll read it understanding its original intent and in a spirit of forgiveness for its shortcomings.
IS SOMETHING ROTTEN IN DENMARK? A SOCIAL NETWORK ANALYSIS OF CONFLICT OF INTEREST IN VACCINE SAFETY RESEARCH
Mark F. Blaxill, M.B.A.
Vice President, SafeMinds
Short title: Commercial conflicts in vaccine safety research
Three papers based on a Danish patient registry argued against a link between mercury-containing vaccines and autism. Following a related analysis of the autism-MMR vaccine link, these studies were published in close succession in prestigious journals, based on marginally differentiated analyses of the same events and prepared by author groups with numerous connections.
Analysis of these publications, their authors and sponsoring institutions reveals a social network with extensive personal and institutional ties. Analysis of the authors and their employers also reveals a pervasive conflict of interest that was not reported in the publishing journals.
All authors in the network have ties, direct or indirect, to a for-profit, state-owned, vaccine manufacturer: the Statens Serum Institut (SSI). The mercury-containing vaccine investigated in the three studies was produced by SSI. Six SSI employees participated as co-authors in studies in which the safety of SSI products were evaluated. These six individuals also hold central positions in a broader network with ties to eleven additional authors and maintain formal alliances at the institutional level.
SSI has a commercial interest in vaccine products: the vaccine division contributed half of SSI’s revenues and over 80% of profits in 2002; vaccine exports were SSI’s fastest growing business; mercury-containing vaccine products support SSI’s vaccine exports; and SSI provides ingredients for mercury-containing vaccines currently used outside Denmark.
SSI has a conflict of interest in conducting assessments of vaccine safety. This conflict should be considered when evaluating the authors’ findings that mercury in Danish vaccines did not cause harm.