Thursday, January 10, 2013

placebo effect

Very cool article on research on the placebo effect itself as a treatment.* (Via Kottke)

It makes me wonder two things in particular. (But read the article; most of it is about other things :)

First, what have drug companies already worked out about the procedural aspects of the placebo effect, in the course of designing RCTs in a way to maximize the chance of an outcome favorable to the drug?** This may not have been considered knowledge of direct interest in the past, but now it clearly is, and I bet they have a wealth of data/local knowledge of value. The article inadvertently makes it clear what great interest they have in placebo effects:
That study ... showed that patients with a certain variation of a gene linked to the release of dopamine were more likely to respond to sham acupuncture than patients with a different variation—findings that could change the way pharmaceutical companies conduct drug trials...Companies spend millions of dollars and often decades testing drugs; every drug must outperform placebos if it is to be marketed. "If we can identify people who have a low predisposition for placebo response, drug companies can preselect for them," says Winkler. "This could seriously reduce the size, cost, and duration of clinical trials…bringing cheaper drugs to the market years earlier than before."

Second, have they looked at Hawthorne / experimenter demand effects? Patients' reports of their symptoms and side effects are quite likely biased, and if they've been told that they should expect something, their reports are likely biased to pay more attention / exaggerate those things. What if they are told (at the time of the report) that they should be as objective and comprehensive as possible in their reports, for the sake of science, because they may or may not have been given the real drug and the doctors need accurate assessments for evaluation? Are reports standardized in such a way to maximize objectivity and comprehensiveness? Are multiple reports made over time to control for individual variation (as the article notes that one of these placebo studies was unique in doing)? Are all reports accompanied by objective physiological measures? The article suggests these things are important, but then implies that the cause is a discrepancy between subjective and objective experience, rather than false subjective reports. Both possibilities should be investigated.***
The researchers had hoped to find improved lung function with both the real and sham treatments; what they found instead was that only the real treatment yielded results—the others showed no significant improvement. Yet when Kaptchuk’s team measured patients’ own assessments of improvement, the researchers found no difference reported between the real and sham treatments: the patients’subjective responses directly contradicted their own objective physical measures...This discrepancy between objective and subjective results is precisely where the danger lies. "Asthma can be fatal. If the patient’s lung function is getting worse but a placebo makes them feel better, they might delay treatment until it is too late."

*I've idly wondered about this previously, but this article suggests that maybe honest expectations, created by directly lying to the patient, are not even necessary to trigger a placebo response after all, contrary to my intuition. Pretty cool.

**Not to necessarily accuse drug companies of anything unethical; you could just as easily describe that as "what situational knowledge, derived from years of experience, have drug companies acquired on how to keep doctor interactions / medical procedures as neutral as possible in order to get the cleanest measure of the impact of a drug"...

***Of course, I'm sure they have been to some degree; I'm commenting on a journalistic treatment, and we all know how reliable/thorough those tend to be...

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