It gets better—or worse, depending on how you feel about your world view slipping sideways. Montgomery and Kirsch [1996] told college students they were taking part in a study on a new local anaesthetic called ‘trivaricaine’. Trivaricaine is brown, you paint it on your skin, it smells like a medicine, and it’s so potent you have to wear gloves when you handle it: or that’s what they implied to the students. In fact it’s made of water, iodine and thyme oil (for the smell), and the experimenter (who also wore a white coat) was only using rubber gloves for a sense of theatre. None of these ingredients will affect pain.
The trivaricaine was painted onto one or other of the subjects’ index fingers, and the experimenters then applied painful pressure with a vice. One after another, in varying orders, pain was applied, trivaricaine was applied, and as you would expect by now, the subjects reported less pain, and less unpleasantness, for the fingers that were pre-treated with the amazing trivaricaine. This is a placebo effect, but the pills have gone now.
It gets stranger. Sham ultrasound is beneficial for dental pain, placebo operations have been shown to be beneficial in knee pain (the surgeon just makes fake 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.
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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.
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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 the placebo effect, and cuts even further into the work of alternative therapists: because we should remember that alternative therapists don’t just give placebo treatments, they also give what we might call ‘placebo explanations’ or ‘placebo diagnoses’: ungrounded, unevidenced, often fantastical assertions about the nature of the patient’s disease, involving magical properties, or energy, or supposed vitamin deficiencies, or ‘imbalances’, which the therapist claims uniquely to understand.
And here, it seems that this ‘placebo’ explanation—even if grounded in sheer fantasy—can be beneficial to a patient, although interestingly, perhaps not without collateral damage, and it must be done delicately: assertively and authoritatively giving someone access to the sick role can also reinforce destructive illness beliefs and behaviours, unnecessarily medicalise symptoms like aching muscles (which for many people are everyday occurrences), and militate against people getting on with life and getting better. It’s a very tricky area.
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About a hundred years ago, these ethical issues were carefully documented by a thoughtful native Canadian Indian called Quesalid. Quesalid was a sceptic: he thought shamanism was bunk, that it only worked through belief, and he went undercover to investigate this idea. He found a shaman who was willing to take him on, and learned all the tricks of the trade, including the classic performance piece where the healer hides a tuft of down in the corner of his mouth, and then, sucking and heaving, right at the peak of his healing ritual, brings it up, covered in blood from where he has discreetly bitten his lip, and solemnly presents it to the onlookers as a pathological specimen, extracted from the body of the afflicted patient.
Quesalid had proof of the fakery, he knew the trick as an insider, and was all set to expose those who carried it out; but as part of his training he had to do a bit of clinical work, and he was summoned by a family ‘who had dreamed of him as their saviour’ to see a patient in distress. He did the trick with the tuft, and was appalled, humbled and amazed to find that his patient got better.
Although he continued to maintain a healthy scepticism about most of his colleagues, Quesalid, to his own surprise perhaps, went on to have a long and productive career as a healer and shaman. The anthropologist Claude Levi-Strauss, in his paper ‘The Sorcerer and his Magic’, doesn’t quite know what to make of it: ‘but it is evident that he carries on his craft conscientiously, takes pride in his achievements, and warmly defends the technique of the bloody down against all rival schools. He seems to have completely lost sight of the fallaciousness of the technique which he had so disparaged at the beginning.’
~~Bad Science -by- Ben Goldacre
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