Authors reject interpretation linking autism and MMR vaccineBMJ 2004; 328 doi: http://dx.doi.org/10.1136/bmj.328.7440.602-c (Published 11 March 2004) Cite this as: BMJ 2004;328:602
Ten of the 13 authors of the research paper that first raised the possibility of a link between the measles, mumps, and rubella (MMR) vaccine and autism (Lancet 1998;351:637-41), resulting in a major fall in the number of children being vaccinated in the United Kingdom, “retracted” this interpretation of their findings in a statement published last week (Lancet 2004;363:750).
They said, “The main thrust of the paper was the first description of an unexpected intestinal lesion in the children reported … 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. However, the possibility of such a link was raised and consequent events have had major implications for public health. In view of this, we consider now is the appropriate time that we should together formally retract the interpretation placed upon these findings in the paper.”
Two of the original authors, Andrew Wakefield and Peter Harvey, did not sign the retraction, and the Lancet said that it hoped to publish their response soon. Another of the authors could not be contacted.
The study investigated 12 children who were referred to a paediatric gastroenterology unit with a history of normal development followed by loss of acquired skills (including language), together with diarrhoea and abdominal pain. All 12 children had intestinal abnormalities, ranging from lymphoid nodular hyperplasia to aphthoid ulceration. Nine of the children were judged to have autism.
The research group, from the Royal Free Hospital and School of Medicine London, reported that in eight of the 12 cases the parents associated the onset of behavioural symptoms with MMR vaccination, while in one case the parents associated it with measles infection and in another with otitis media.
In the paper the researchers concluded that they had “identified associated gastrointestinal disease and developmental regression in a group of previously normal children, which was generally associated in time with possible environmental triggers.” In their discussion of the findings they reviewed previous research associating rubella virus and the combined MMR vaccine and autism, but they cautioned: “We did not prove an association between measles, mumps and rubella vaccine and the syndrome described.”
However, one of the group, Andrew Wakefield, suggested at a press conference about the study that there might be a link and that parents should consider single vaccinations for measles, mumps, and rubella rather than the combined triple vaccine. This suggestion led to a major loss of public confidence in the combined vaccine, and vaccination rates fell in the United Kingdom, with annual NHS immunisation statistics for England showing that at March 2003 only 82% of children aged two years had been vaccinated with the MMR vaccine.
Commenting on the issue, the editor of the Lancet, Dr Richard Horton, said that the retraction came after the recent release of information showing that Dr Wakefield had received £55 000 ($101 000; €82 000) from the Legal Aid Board to investigate a possible claim against the manufacturers of the vaccine—a claim involving some of the children in the study. This was a financial conflict of interest that should have been declared to the editors but was not (Lancet 2004;363:820-1).
In a separate commentary in the journal Dr Horton suggested that current mechanisms failed to deal adequately with allegations of research misconduct, and he called for a national body—an independent council of research integrity—to investigate allegations of serious research misconduct (Lancet 2004;363:747).
He considered that important lessons were to be learned about how scientific research impacts on the public. Medical journals should continue to publish original and sometimes unpopular ideas in responsible ways, he said, but he argued that they must take greater care to consider the impact on the public of the work they print.
He concluded: “Information that once could be confined to a small community of professionals is now open to wider distribution and comment—accurately or otherwise. This places great responsibility on editors, scientists, and press and public-relations professionals to avoid encouraging anybody to go beyond the data or interpretations described in a paper.”
Professor Sian Griffiths, president of the Faculty of Public Health, the body representing public health doctors, said: “It is shame that the poor science in this study—which has been recognised from its publication—was not communicated clearly to the media and the public. This has meant that a formal retraction from the researchers has been required to make it clear.
“There is now a duty to ensure that the public are fully aware of this retraction. Professionals may know about it, but do parents?”
She considered that the impact of the research study had been “incredibly damaging for public health” and considered that scientists and journals should be very careful about promoting research findings to the media, given the risk that hypotheses might be misinterpreted as facts.
Dr Ian Gibson, chair of the House of Commons Science and Technology committee was disparaging about the decision to retract merely the implications placed upon the findings in the paper, rather than the entire paper.
“How can you partially retract something?” he asked. “I think they should have retracted the whole paper.
“You don't publish papers like that with all sorts of ideas. I'm surprised they got it through the peer review process. I think they [the Lancet] should have held back and asked for further work to be done on it. It is a sample of 12. They have got to be very, very careful.
“I think the real question is about the role of the editorial board and the editor in chief. They really ought to have had more proof before they published it, especially in the medical arena, and especially with vaccines.”
He said his committee intended to write to the Lancet and other medical journals, including the BMJ, outlining their concerns.