From Simon Perry:
If you've not vaccinated your child against MMR as a result of the media outcry, read on.
It started with a class action lawsuit.
A number of parents, convinced that their children's autism had been caused by the MMR vaccine, decided to sue the vaccine's manufacturer.
But the parents had one problem: their claim of a link between MMR and autism was based upon nothing but intuition. The lawyers needed scientific research that demonstrated a link.
And who better to provide that research than Dr Andrew Wakefield?
Wakefield wouldn't seem to be an obvious choice, given that he did not have the necessary paediatric qualifications, but one thing Wakefield did possess was bias in their favour.
After all, he was the inventor of an alternative vaccine for the measles virus.
In total, Wakefield was paid more than £435,000 by Legal Aid to provide evidence to the court, according to the results of a Freedom of Information request.
Wakefield's team dealt with 12 children between the ages of three and 10.
His research involved sedating them and subjecting them to ileocolonoscopy, an endoscopic examination of the large bowel and part of the small bowel, which included taking a biopsy from their small intestine.
It also involved lumbar puncture, commonly known as a spinal tap.
To discover if the symptoms found were correlated with the MMR vaccine, Wakefield's team simply asked the parents and physicians if the onset of the symptoms occurred soon after the child was given the vaccine.
But the first stage was to find children to assess. This can be one of the trickiest bits of getting the science right, because the way that your sample group is selected can easily introduce bias in your results, even if you are extremely careful to avoid it.
By looking for children whose parents already blamed their child's symptoms on the MMR vaccine, it appears Wakefield was guaranteed an outcome that would please the legal team.
Wakefield's paper claimed that the children had been consecutively referred to the Department of Paediatric Gastroenterology with a history of a pervasive developmental disorder and intestinal symptoms.
We later found out that Wakefield had been actively involved in getting these children referred.
In fact, some of the children had been actively recruited through anti-MMR campaign groups, and most of the parents were clients and contacts of the very lawyer who commissioned Wakefield with an aim to "produce unassailable evidence in court so as to convince a court that these vaccines are dangerous".
One parent was even the managing director of the company set up to sell Wakefield's alternative vaccine.
The results were as predictable as an election poll that only polled members of, say, the Green Party, and equally inaccurate in describing reality.
Now you can criticise me for being judgemental if you like, but if you wish to stick a needle into a three-year-old's spine and then force something large and uncomfortable into their anus then you'd better have a very good reason for doing so.
Producing dodgy research for a lawsuit is not, in my opinion, reason enough.
While the risks involved in colonoscopy are small, they certainly exist.
In December, 2007, the Daily Mail reported that in a similar procedure that followed the initial "research", a 14-year-old boy had a similar unnecessary procedure and endured multiple organ failure after his bowel was perforated in 12 places.
Wakefield managed to get his paper published in The Lancet in February, 1998.
However, the paper had certain critical elements missing.
It didn't mention the conflicts of interest that would have caused his paper to be rejected. It didn't mention how the children had been selected. After suggestions that the process had been biased, Wakefield responded in a published letter that the children had been referred through the normal channels – a statement described by the GMC as "dishonest and irresponsible".
At the time the paper was published, nobody knew about what was going on behind the scenes. Even if this research had been conducted honestly, it still would not tell us anything useful about the MMR vaccine.
If you take 12 patients who were referred to a ward for specific symptoms, then you really shouldn't be surprised if you find out that many of them have those symptoms.
You also shouldn't be too surprised if they'd also had the MMR vaccine when, in 1996, 96% of children had received it.
The evidence consisted of no more than eight anecdotes from a possible 12. This paper was effectively worthless.
There was never, at any point in this hoax, a single point in time where it would have been reasonable to believe it to be likely that there was a connection between MMR and autism, yet this did not stop newspapers repeating the story and misinterpreting the evidence.
Possibly as a direct result of the media outcry following Wakefield's flawed research, other scientists were motivated to find out if there was a genuine link.
And in contrast to Wakefield, they managed to do it without putting a single piece of medical equipment up a child's bottom.
In November, 2002, Madsen, Hviid, Vestergaard et al compared levels of autism in children who had received the MMR jab against those who hadn't.
Instead of Wakefield's 12 children, this study used 537,303.
And instead of selecting them specifically to prove the outcome they hoped for, they used every child born in Denmark from 1991 through 1998.
There was no difference in the rates of autism in the two groups.
The authors quite reasonably concluded "This study provides strong evidence against the hypothesis that MMR vaccination causes autism".
This was by no means the only study. In 2008, a Cochrane review looked at 31 separate studies and concluded that "no credible evidence of an involvement of MMR with either autism or Crohn's disease was found."
In 1996, 92% of children were vaccinated with MMR. In 2002, it was down to just 84%. And in 2006 – more than three years after the Danish study of 537,303 children was published and two years after Brian Deer uncovered the flaws at the heart of Wakefield's 12 case studies – MMR coverage at 24 months was just 85%.
In 2006, measles came back to the UK.
In 2005, we had just 77 cases. In 2006, there were 449 before April. One child died. The mumps epidemic of 2005 infected 56,390 people.
There is only one way to prevent future epidemics. Vaccinate your children.
Brian Deer, the investigative journalist who exposed Wakefield's research, will be speaking at Leicester Skeptics in the Pub on July 15.
It starts at 7:30pm in Square Bar on Hotel Street, Leicester.
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