The MMR vaccine and autism: Sensation, refutation, retraction, and fraud
In 1998, Andrew Wakefield and 12 of his colleagues published a case series in the Lancet, which suggested that the measles, mumps, and rubella (MMR) vaccine may predispose to behavioral regression and pervasive developmental disorder in children. Despite the small sample size (n=12), the uncontrolled design, and the speculative nature of the conclusions, the paper received wide publicity, and MMR vaccination rates began to drop because parents were concerned about the risk of autism after vaccination.
Almost immediately afterward, epidemiological studies were conducted and published, refuting the posited link between MMR vaccination and autism.[3,4] The logic that the MMR vaccine may trigger autism was also questioned because a temporal link between the two is almost predestined: both events, by design (MMR vaccine) or definition (autism), occur in early childhood.
The next episode in the saga was a short retraction of the interpretation of the original data by 10 of the 12 co-authors of the paper. According to the retraction, “no causal link was established between MMR vaccine and autism as the data were insufficient”. This was accompanied by an admission by the Lancet that Wakefield et al. had failed to disclose financial interests (e.g., Wakefield had been funded by lawyers who had been engaged by parents in lawsuits against vaccine-producing companies). However, the Lancet exonerated Wakefield and his colleagues from charges of ethical violations and scientific misconduct.
The Lancet completely retracted the Wakefield et al. paper in February 2010, admitting that several elements in the paper were incorrect, contrary to the findings of the earlier investigation. Wakefield et al. were held guilty of ethical violations (they had conducted invasive investigations on the children without obtaining the necessary ethical clearances) and scientific misrepresentation (they reported that their sampling was consecutive when, in fact, it was selective). This retraction was published as a small, anonymous paragraph in the journal, on behalf of the editors.
The final episode in the saga is the revelation that Wakefield et al. were guilty of deliberate fraud (they picked and chose data that suited their case; they falsified facts). The British Medical Journal has published a series of articles on the exposure of the fraud, which appears to have taken place for financial gain.[10–13] It is a matter of concern that the exposé was a result of journalistic investigation, rather than academic vigilance followed by the institution of corrective measures. Readers may be interested to learn that the journalist on the Wakefield case, Brian Deer, had earlier reported on the false implication of thiomersal (in vaccines) in the etiology of autism. However, Deer had not played an investigative role in that report.
The systematic failures which permitted the Wakefield fraud were discussed by Opel et al.