Controversial MMR and autism study retracted
- 13:08 04 March 2004
- NewScientist.com news service
- Maggie McKee
Ten of the original 13 authors of a controversial 1998 medical report which implied a link between autism and the combined MMR vaccine for measles, mumps, and rubella, have retracted the paper's interpretations.
The retraction will be printed in the 6 March issue of The Lancet, which published the original paper. One author could not be reached and two others, Peter Harvey and lead author Andrew Wakefield, refused to join the retraction.
"We wish to make it clear that in this paper no causal link was established between MMR vaccine and autism as the data were insufficient," write the 10 authors in their retraction. "However, the possibility of such a link was raised and consequent events have had major implications for public health."
The original paper, which was based on parental and medical reports of just a dozen children, suggested a "possible relation" between autism, bowel disease, and MMR. The paper added it "did not prove an association".
However, Wakefield argued in a press conference at the time that there was a case for giving children separate injections for measles, mumps, and rubella instead of a single shot for all three. This triggered a collapse in parental confidence in MMR, and uptake rates of the vaccine in the UK fell.
The retraction "is to be strongly welcomed", says Brent Taylor, head of pediatrics and child health at the UK's University College London. "There is overwhelming evidence that MMR vaccine does not cause autism," Taylor told New Scientist, citing several of his own studies. "This disputed paper is the only evidence in the mainstream medical press that it might."
In the six years since the paper's publication, MMR vaccination rates in the UK have dropped from more than 90 per cent to less than 80 per cent. "We are expecting outbreaks of measles and mumps and a return of congenital rubella," says Taylor.
In a commentary accompanying the retraction, the journal's editor Richard Horton emphasised the retraction is partial and that the possible link between bowel disease and autism raised in the original paper "is a serious scientific idea ... that deserves further investigation".
He defends forums that "raise new and sometimes unpopular thinking" but says "how we discuss this new thinking then becomes the central question to answer, not whether we should publish it or not". He suggests a neutral, non-governmental organisation such as the UK's Consumers' Association might provide a trusted and impartial public health forum.
The Lancet has been embroiled in what Horton calls an "enormously confusing" debate in recent weeks after media reports revealed Wakefield did not disclose financial and professional conflicts of interest in the original paper. The UK's medical oversight body, the General Medical Council, is considering an investigation of these charges. They include the fact that Wakefield received £55,000 from the UK's legal aid board for another study to investigate whether parents had a basis to sue over a possible connection between MMR and autism.
Journal reference: The Lancet (vol 363, p 747)