Map of life expectancy at birth from Global Education Project.

Thursday, July 26, 2007

Aimless chatter

1) You've probably heard about the study in the new NEJM, to the effect that if your siblings and friends get fat, you're likely to do the same. I've had a chance to read the whole thing, and it's certainly sound research. They had the benefit of data from the Framingham Heart Study, a long-term, large-scale prospective cohort study that's been following thousands of people, and now their descendants, for decades. It's unique, which means, alas, that this study is probably not reproducible.

The limitation, of course, is that this study cannot tell us why this happens. The authors speculate that it more or less comes down to the idea of setting a bad example (although they don't like to put it in such invidious terms). In other words, if you see your buddies get fat, you start to feel like it's okay. Could be. But we know that it's very hard to control weight through conscious effort, so this has the perhaps counterintuitive implication that unconscious influences are more powerful than intentional effort. Or does it? Maybe it points to the importance of motivation.

2) In the same issue, George Annas discusses efforts by advocacy groups to give people with advanced cancer access to experimental treatments outside of clinical trials. Most people's instincts about this are both libertarian and compassionate -- the people are dying, for heaven's sake, if they want to try something let them, the worst that can happen is they'll die which they are doing anyway.

Annas goes through various complex arguments about how such a policy would metastasize throughout the legal regime -- in a nutshell, how do you limit it to the dying and to drugs that at least have been through Phase I trials -- causing all kinds of mischief. But the bottom line objection that's going to make sense to most people, I hope, is that such a policy would make it difficult if not impossible to develop effective treatments for broad use. The reason is that the only way we can establish whether a treatment is truly effective is through controlled trials -- half the people have to get the placebo. If everybody with terminal cancer is allowed to take investigational drugs, nobody will accept the placebo. But the fact is, most investigational drugs don't work, or they do more harm than good, so you really aren't doing anybody any favors by letting them have them. (Theoretically, in order to do a controlled trial, you need to have a condition called clinical equipoise: you really don't know whether one condition is better than the other.) So there is a huge cost to society in such a policy, and it doesn't actually benefit the individual whose liberty interest we think we are honoring.

3) The zombie autism/MMR thing is back. In the new BMJ, Ben Goldacre tells the appalling story of an article in the UK's Observer newspaper that claimed new research had found the prevalence of autism to be much higher than previously believed -- 1 in 58 -- and that "leading researchers" thought this might be due to the MMR vaccine. None of the above was true. Period. The article can only be described as hoax. The study found no such thing, one of the "leading researchers" had no such opinion, and the other, who is not even part of the study team, works for Andrew Wakefield, the doctor who started the whole thing with a fraudulent paper in The Lancet many years ago, which has been withdrawn. Wakefield is now in the U.S., continuing to rob desperate parents with his crackpot theories. Goldacre concludes:

Whatever one might think about Andrew Wakefield, he was just one man: The MMR autism scare has been driven for a decade now by a media that over-emphasises marginal views, misrepresenting and cherry picking research data to suit its cause. As the Observer scandal makes clear, there is no sign this will stop.

4) Still slogging through the Bible. Check it out if you find that sort of thing interesting. (If you can't blogwhore on your own blog, where can you blogwhore?)

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