More and more these days I notice parents who refuse to have their children vaccinated for measles, mumps and rubella because they have heard that the vaccine causes autism. They are all shockingly uninformed, but don't realize it. Part of the problem lies in the fact that they don't realize the one bit of highly publicized research evidence that supports the autism link is riddled with multiple and damning problems. And just this week, it got a lot, lot worse.
According to an investigation by the Sunday Times newspaper, the doctor who sparked the scare over the safety of the MMR vaccine, Andrew Wakefield, fabricated the data that created the appearance of a possible link with autism. He lied. You can read the full article here.
Compared to lying, the other problems with Wakefield's research seem minor in comparison. But nevertheless, even if the results were not made up, the fake-o numbers still do not in any way warrant the autism hysteria that has erupted over vaccines.
And the effect of the hysteria is significant. After the publication of Wakefield's research in 1998, rates of vaccination fell from 92% to below 80% in the UK, according to the Times. And in just ten years, the number of confirmed cases of measles skyrocketed to 1,348 compared with just 56 in 1998.
Aside from the glaring problem with using fabricated data, the other problems with Wakefield's research are threefold, scratch that fourfold!
1. extremely small sample size: The research included only 12 kids!
2. relied on retrospective evidence: Rather than starting out with a sample of children who neither had autism nor had yet been vaccinated, the study used parents who reported autism symptoms after the child was vaccinated. In other words, the researchers relied on parents of autistic children’s memories of events — parents who were understandably upset and far from objective observers.
3. biased sample, i.e. not randomly selected: Almost half of the kids' parents were recruited by a lawyer who planned to sue the vaccine manufacturers. Even Wakefield himself received money to assist the case by finding scientific evidence of the link between autism and the vaccine. You can read more about that here.
One reason some parents think vaccines caused their child's autism is the timing of diagnosis. The first signs of autism don't appear until around 18 months to 2 years of age, the same time period in which kids are vaccinated. It is this unfortunate timing that makes parents think the vaccines caused the condition. Another case of erroneous correlation = causation thinking.
If vaccines really were causing autism, you'd at least expect to see the incidence of autism rise and fall with the rise and fall of vaccination rates — but it doesn't. You can read the published research yourself here. The article also has an impressive list of other relevant research articles on the subject. I think it's pretty much overwhelming evidence that something other than vaccines causes autism.