“You cannot reason people out of positions they didn’t reason themselves into.”
— Ben Goldacre, MD
Dr. Ben Goldacre is the author of the popular Guardian column, Bad Science. He has recently published a book by the same name. Bad Science received a very favorable review from the British Medical Journal and although I was tempted to write my own review for Science Based Medicine, I decided to cherry pick some concepts from the book instead. I hope you’ll enjoy the cherries.
Honesty & Placebos
As you can imagine, any good book about bad science must devote at least one chapter to the concept of placebos. We are all quite familiar with placebos, and how squarely the vast majority (and some would argue all) of complementary and alternative medicines fit into that category. Ben surprised me with a couple of points that I hadn’t considered previously. Firstly, that alerting patients to the fact that you’re planning to prescribe them a placebo does not necessarily negate its effects, and secondly that no matter how skeptical or intelligent you are – all humans are subject to placebo effects.
Ben references a 1965 study from Johns Hopkins [Park et al., Archives of General Psychiatry] in which patients were explicitly told that they were going to receive a sugar pill (with no medicine in it at all) as treatment for their neuroses. The researchers reported substantial improvements in many of the study subjects’ symptoms.
This is the script that the physicians were to use to explain the placebos to the study subjects:
Mr. Doe… we have a week between now and your next appointment, and we would like to do something to give you some relief from your symptoms. Many different kinds of tranquilizers and similar pills have been used for conditions such as yours, and many of them have helped. Many people with your kind of condition have also been helped by what are sometimes called ‘sugar pills,’ and we feel that a so-called sugar pill may help you too. Do you know what a sugar pill is? A sugar pill is a pill with no medicine in it at all. I think this pill will help you as it has helped so many others. Are you willing to try this pill?
Wow. I was under the impression that the efficacy of the placebo was in the person’s belief that it was a legitimate medicine/therapy. Perhaps it only matters that the prescribing physician believes it might help? Perhaps snake oil salesmen are wasting their time on linguistic and pseudoscientific mental gymnastics?
Of course, the “gymnastics” do help. Other research has shown that the more complex the associated placebo ritual, the more potent its effects (such as piercing the skin with fine needles in many different locations). Nonetheless, I was surprised that an honest and accurate description of a placebo does not necessarily negate its effects.