Why do so many people believe vaccines are dangerous? How do we explain the popularity of homeopathic remedies or the widespread publication of misleading drug trials? In Canada to promote his book, Ben Goldacre, a British doctor and author of The Guardian's Bad Science column, outlined the main causes of misleading medical information.
"People are absolutely obsessed with what's good for them or bad for them and understandably so, and evidence-based science is how we arrive at those conclusions. But there's a failure of knowledge about the mechanics of evidence-based science: how to run a clinical trial so it is a fair test; how to make sure it's blinded, it's properly randomized. That is how we know if treatments work or don't work. I think it's weird we don't teach it in school: It's a real educational blind-spot. It's how we know if a drug works, if something in the environment is dangerous. It seems to me that's something schools should want to teach. They're constantly worrying about how to make science education more relevant, and this is clearly the answer."
"Quacks and big pharmaceutical companies use the same tricks to distort the evidence. One of the tricks they use routinely is cherry-picking their results. They only quote studies that give results in their favour, and they ignore studies that show the treatment is a complete waste of time. With kids, I'll give them two big jars filled with blue beads. In each jar, 20 per cent of the beads are yellow. You give the children two cups that they dig into each jar and pull out 50 beads. In each sample you'd expect to get 10 yellow beads. But just from the random play of chance, sometimes you're going to get seven yellow beads in the left hand and 12 in the right hand. Now imagine if those were two groups in a cancer drug trial and the yellow beads are the people dying of cancer. The ones on the left got the cancer drug and the ones on the right didn't. With one jar you would think this drug is a miracle cure, and with the other you wouldn't think it works at all. In the classroom, the kids will quickly realize they have to add up all their results to know the real answer: that there's no difference between the two groups. That doesn't happen in the real world. Cherry-picking results is not something marginal, it's actually a core practice."
Pharmaceutical free rein
"There's no doubt in my mind that the greatest scandal of regulation and ethics is that pharmaceutical companies are allowed to bury the results of drug trials. It's insane and it's on-going. You need absolute, unambiguous, international legislation saying every drug company is compelled to release every piece of trial data they have on a drug. Of course, with the regulation of any business, you have to draw a proportionate line. With drug companies, there are all kinds of things they can still muck around with for profit. You can mislead people with your advertisements, you can cajole people, you can slip doctors cash in envelopes. But the only thing doctors have to make a decision on whether a treatment is effective for their patients is the trial data. If you withhold the trial data, that is tantamount to research fraud."
"I read a recent story about the benefits of Vitamin D. What I want to know is, what were the parameters of the study? What are the other factors? Maybe people who have low vitamin D are also poorer, smokers, any number of other things. It's very unusual that somebody just has a poor diet. Have there been trials? What were the results? Who funded them? I don't think you can regulate journalists, saying they can't write things that aren't quite right. But I think it's a funny time we live in when journalists don't read press releases critically. When you get a press release from a political party, you fact-check. That's what journalism is all about. But a lot of the time in health reporting, this isn't done."
Bad ideas without borders
"In America, a lot of the anxiety about vaccines was driven by fears about a certain preservative that people thought caused autism. The American government looked at all the fuss, looked at the evidence and said "There's no evidence it causes autism, but if you're all going to get so [upset] about it, it doesn't make any difference to us, we'll take it out." And you can see why they would do that. But meanwhile, in Africa, people are starting to say, "Why do we have this in our vaccines?" In Africa, people reuse vaccine bottles, so the preservative is actually essential. But now people say, "We know it's dangerous because the Americans took it out. If it's too dangerous for them, why do we get it here?" Vaccination isn't the most important public health issue in the West, but in Africa it makes a really big difference. The WHO schedule for eradicating polio from the globe was on target for success until 2004, when there was a vaccine scare in Nigeria."
Smart people believe stupid things
"People need to be disabused of their misunderstandings. Health scares can be driven by political and social and cultural factors, rather than by the evidence. The measles vaccine and autism scare kicked off in the U.K. in 2001. In France, people thought the hepatitis B vaccine caused multiple sclerosis. I bet you've never heard that. I think that for a lot of people within the health industry, there's something undignified about engaging with rumours, but we have to."
Siri Agrell is a Globe and Mail reporter.
This interview has been edited and condensed.