Bad Science - Ben Goldacre

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keyhole surgery holes in the side and mucks about for a bit as if he’s doing something useful), and placebo operations have even been shown to improve angina.

      That’s a pretty big deal. Angina is the pain you get when there’s not enough oxygen getting to your heart muscle for the work it’s doing. That’s why it gets worse with exercise: because you’re demanding more work from the heart muscle. You might get a similar pain in your thighs after bounding up ten flights of stairs, depending on how fit you are.

      Treatments that help angina usually work by dilating the blood vessels to the heart, and a group of chemicals called nitrates are used for this purpose very frequently. They relax the smooth muscle in the body, which dilates the arteries so more blood can get through (they also relax other bits of smooth muscle in the body, including your anal sphincter, which is why a variant is sold as ‘liquid gold’ in sex shops).

      In the 1950s there was an idea that you could get blood vessels in the heart to grow back, and thicker, if you tied off an artery on the front of the chest wall that wasn’t very important, but which branched off the main heart arteries. The idea was that this would send messages back to the main branch of the artery, telling it that more artery growth was needed, so the body would be tricked.

      Unfortunately this idea turned out to be nonsense, but only after a fashion. In 1959 a placebo-controlled trial of the operation was performed: in some operations they did the whole thing properly, but in the ‘placebo’ operations they went through the motions but didn’t tie off any arteries. It was found that the placebo operation was just as good as the real one—people seemed to get a bit better in both cases, and there was little difference between the groups—but the most strange thing about the whole affair was that nobody made a fuss at the time: the real operation wasn’t any better than a sham operation, sure, but how could we explain the fact that people had been sensing an improvement from the operation for a very long time? Nobody thought of the power of placebo. The operation was simply binned.

      That’s not the only time a placebo benefit has been found at the more dramatic end of the medical spectrum. A Swedish study in the late 1990s showed that patients who had pacemakers installed, but not switched on, did better than they were doing before (although they didn’t do as well as people with working pacemakers inside them, to be clear). Even more recently, one study of a very hi-tech ‘angioplasty’ treatment, involving a large and sciencey-looking laser catheter, showed that sham treatment was almost as effective as the full procedure.

      ‘Electrical machines have great appeal to patients,’ wrote Dr Alan Johnson in the Lancet in 1994 about this trial, ‘and recently anything to do with the word LASER attached to it has caught the imagination.’ He’s not wrong. I went to visit Lilias Curtin once (she’s Cherie Booth’s alternative therapist), and she did Gem Therapy on me, with a big shiny science machine that shone different-coloured beams of light onto my chest. It’s hard not to see the appeal of things like Gem Therapy in the context of the laser catheter experiment. In fact, the way the evidence is stacking up, it’s hard not to see all the claims of alternative therapists, for all their wild, wonderful, authoritative and empathic interventions, in the context of this chapter.

      In fact, even the lifestyle gurus get a look in, in the form of an elegant study which examined the effect of simply being told that you are doing something healthy. Eighty-four female room attendants working in various hotels were divided into two groups: one group was told that cleaning hotel rooms is ‘good exercise’ and ‘satisfies the Surgeon General’s recommendations for an active lifestyle’, along with elaborate explanations of how and why; the ‘control’ group did not receive this cheering information, and just carried on cleaning hotel rooms. Four weeks later, the ‘informed’ group perceived themselves to be getting significantly more exercise than before, and showed a significant decrease in weight, body fat, waist-to-hip ratio and body mass index, but amazingly, both groups were still reporting the same amount of activity.*

       What the doctor says

      If you can believe fervently in your treatment, even though controlled tests show that it is quite useless, then your results are much better, your patients are much better, and your income is much better too. I believe this accounts for the remarkable success of some of the less gifted, but more credulous members of our profession, and also for the violent dislike of statistics and controlled tests which fashionable and successful doctors are accustomed to display.

      Richard Asher, Talking Sense, Pitman Medical, London, 1972

      As you will now be realising, in the study of expectation and belief, we can move away from pills and devices entirely. It turns out, for example, that what the doctor says, and what the doctor believes, both have an effect on healing. If that sounds obvious, I should say they have an effect which has been measured, elegantly, in carefully designed trials.

      Gryll and Katahn [1978] gave patients a sugar pill before a dental injection, but the doctors who were handing out the pill gave it in one of two different ways: either with an outrageous oversell (‘This is a recently developed pill that’s been shown to be very effective … effective almost immediately…’); or downplayed, with an undersell (‘This is a recently developed pill … personally I’ve not found it to be very effective…’). The pills which were handed out with the positive message were associated with less fear, less anxiety and less pain.

      Even if he says nothing, what the doctor knows can affect treatment outcomes: the information leaks out, in mannerisms, affect, eyebrows and nervous smiles, as Gracely [1985] demonstrated with a truly ingenious experiment, although understanding it requires a tiny bit of concentration.

      He took patients having their wisdom teeth removed, and split them randomly into three treatment groups: they would have either salt water (a placebo that does ‘nothing’, at least not physiologically), or fentanyl (an excellent opiate painkiller, with a black-market retail value to prove it), or naloxone (an opiate receptor blocker that would actually increase the pain).

      In all cases the doctors were blinded to which of the three treatments they were giving to each patient: but Gracely was really studying the effect of his doctors’ beliefs, so the groups were further divided in half again. In the first group, the doctors giving the treatment were told, truthfully, that they could be administering either placebo, or naloxone, or the pain-relieving fentanyl: this group of doctors knew there was a chance that they were giving something that would reduce pain.

      In the second group, the doctors were lied to: they were told they were giving either placebo or naloxone, two things that could only do nothing, or actively make the pain worse. But in fact, without the doctors’ knowledge, some of their patients were actually getting the pain-relieving fentanyl. As you would expect by now, just through manipulating what the doctors believed about the injection they were giving, even though they were forbidden from vocalising their beliefs to the patients, there was a difference in outcome between the two groups: the first group experienced significantly less pain. This difference had nothing to do with what actual medicine was being given, or even with what information the patients knew: it was entirely down to what the doctors knew. Perhaps they winced when they gave the injection. I think you might have.

       ‘Placebo explanations’

      Even if they do nothing, doctors, by their manner alone, can reassure. And even reassurance can in some senses be broken down into informative constituent parts. In 1987, Thomas showed that simply giving a diagnosis—even a fake ‘placebo’ diagnosis—improved patient outcomes. Two hundred patients with abnormal symptoms, but no signs of any concrete medical diagnosis, were divided randomly into two groups. The patients in one group were told, ‘I cannot be certain of what the matter is with you,’ and two weeks later only 39 per cent were better; the other group were given a firm diagnosis, with no messing about, and confidently told they would be better within a few days. Sixty-four per cent of that group got better in two weeks.

      This raises the spectre of something way beyond

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