A controversial 1998 study published in The Lancet implied that the MMR vaccine might be a cause of autism. This sparked deep suspicion of the vaccine and prompted a great deal of new research involving hundreds of thousands of children (that has been unable to find any such connection). The original study included only a dozen children, and was based partly on parents’ reports.
In 2004, serious allegations were raised against this original paper, asserting that the dozen children selected in the study were not randomly chosen as described in the paper, but included children involved in a legal action claiming vaccine injury. Perhaps the parents’ reports were biased – but either way, the possible conflict of interest was not disclosed. Nor was the money received by the lead investigator for helping to prepare the legal action. The Lancet has investigated these claims and issued a partial retraction of the original paper in the March 6, 2004 issue. Ten of the original 13 authors of the paper have retracted the paper’s conclusions. I’m in favor of publishing controversial ideas and studies, to provoke discussion and research. But it’s important for the readers to have access to possible financial motives that may introduce bias into the discussion.