Bad Science

by Ben Goldacre

We know that two sugar pills are a more effective treatment than one sugar pill, for example, and we know that salt-water injections are a more effective treatment for pain than sugar pills, not because salt-water injections have any biological action on the body, but because an injection feels like a more dramatic intervention. We know that the colour of pills, their packaging, how much you pay for them and even the beliefs of the people handing the pills over are all important factors. We know that placebo operations can be effective for knee pain, and even for angina. The placebo effect works on animals and children. It is highly potent, and very sneaky,

Ben Goldacre on the placebo effect.

Let’s say you have a cold. It’s going to get better after a few days, but at the moment you feel miserable. It’s quite natural that when your symptoms are at their very worst, you will do things to try to get better. You might take a homeopathic remedy. You might sacrifice a goat and dangle its entrails around your neck. You might bully your GP into giving you antibiotics. (I’ve listed these in order of increasing ridiculousness.) Then, when you get better—as you surely will from a cold—you will naturally assume that whatever you did when your symptoms were at their worst must be the reason for your recovery. Post hoc ergo propter hoc, and all that.

Regression to the mean.

Just as the Big Bang theory is far more interesting than the creation story in Genesis, so the story that science can tell us about the natural world is far more interesting than any fable about magic pills concocted by an alternative therapist.

There are few opinions so absurd that you couldn’t find at least one person with a PhD somewhere in the world to endorse them for you; and similarly, there are few propositions in medicine so ridiculous that you couldn’t conjure up some kind of published experimental evidence somewhere to support them, if you didn’t mind it being a tenuous relationship, and cherry-picked the literature, quoting only the studies that were in your favour.

people who are incompetent suffer a dual burden: not only are they incompetent, but they may also be too incompetent to assay their own incompetence, because the skills which underlie an ability to make a correct judgement are the same as the skills required to recognise a correct judgement.