blogs.forbes.com/robertlangreth/2010/12/28/harvard-placebo-study-was-seriously-overhyped -> blogs.forbes.com/robertlangreth/2010/12/28/harvard-placebo-study-was-seriously-overhyped/
But now skeptical bloggers are attacking its conclusions and saying they are seriously exaggerated and prove just about nothing. After reading the skeptics, I tend to agree that the study is not as impressive as it first seemed.
comment on my blog: There are multiple problems with this study. And then the results are marginal at best - slightly better improvement in the placebo group vs the "no treatment" group.
php), the two groups weren't at all balanced, so that simple biases may explain the different outcomes. Fourth, the authors are strong proponents of "alternative" (ie, quack) medical treatments, and they have a strong bias towards claiming that placebo effects are some kind of ill-defined mind-body effect (which they claim in the discussion). So my take is: poorly done study, published in a relatively uncompetitive journal (PLoS ONE), with a small effect. The authors are boasting about it and getting more attention than it deserves.
Sugar Pills Work Even When People Know They Are Fake One serious criticism is that despite the claim that 59% of irritable bowel patients who got placebo pills got better versus only 35% who took nothing got better, when you look more closely at the data, the difference between the two groups was surprisingly small. In one scale there was a 5 point improvement in symptoms in the placebo pill group, but people who got nothing had a 4 point improvement over the same period of time This suggests that the main effect here is the passage of time. Just buy waiting a few weeks your IBS symptoms subside substantially. If you get all jazzed up about a mysterious placebo effect, that positive thinking may help you feel even slightly better on subjective scales. But the main effect is just the passage of time-you go into the doctor when the symptoms are the worst, and naturally the get better the next few weeks no matter what you do. Of course you feel better if your doctor is telling you about some powerful proven placebo that is proven to have significant effects.
his own blog at ScienceBlogs: In contrast, Kaptchuk et al explicitly deceived their subjects for purposes of the study by telling them that the sugar pill activated some sort of mind-body woo that would make them feel better Yes, they did tell the subjects that they didn't have to believe in mind-body interactions. I doubt it, because people with authority, whom patients tend to believe (namely doctors) also told subjects that evidence showed that these placebo pills activated some sort of "mind-body" mechanism that was described as "powerful." The biggest problem I have is with how the study is being sold to the press, as though it were evidence that placebo effects can really be triggered without at least some degree of deception. Basically, Orac is saying that contrary to its claims, the study still involved deception, in the same way that a used car dealer can technically disclose to you that the car he is selling to you is a piece of junk, while at the same time he is talking the cars merits up so excitedly you hardly notice you are buying a lemon. The used car dealer may feel better because, legally speaking, he has disclosed to you that the car is garbage. But the excitement in his voice and the glint in his eyes and the cool adjectives that he is using-the sales pitch-is what is selling you the car, not the legal documents or the actual words that say you are buying a worthless piece of junk. Orac is arguing that the Harvard study involved doctors giving a deceptive sales pitch about the amazing powers of placebo even as they technically told the people they were getting an inert pill. After such a sales pitch, I wonder if the researchers had surveyed the participants, how many of them would have answered "true" to the blunt questions "these pills that I have been taking are totally inert and contain no active ingredients that could possibly impact my health in any objective way" or "there is no chemical or active drug inside these pills that will treat my irritable bowel"? Yes, your doctor telling you that he has something for you that will make you feel a little better, puts you in a better mood, stops your worry, and makes your vague subjective symptoms feel a little better! This is especially true if you ask really vague questions, like overall, do you feel better as opposed to more specific or objective questions. That is hardly the same as saying there is some mysterious mind-body placebo effect that could help treat all sorts of everyday ailments. I think much of what passes for placebo effect over the long term is simply the fact that symptoms improve over time, and happiness that the doctor is taking you seriously and really trying to help. I would love to get a response from one of the researchers involved in the study.
ssilberman Robert, while some of Orac's criticisms seem valid, you're front-loading bias of your own by characterizing the subject of this study as a "mysterious placebo effect that produces all sorts of miraculous effects." There's nothing mysterious or miraculous about the placebo effect. It's a set of physiological responses to a known set of stimuli like any other.
html What isn't proven yet is how these potentially therapeutic responses work in day-to-day medical practice. For the record, the critique of Orac's that you called "the most serious criticism of the study" struck me as the most specious and circular: define the placebo effect as unproven, declare telling patients about it a lie, and brand the premise of the whole study as a fraud. But there's plenty of proof that the placebo response is real, as Benedetti's paper (and many others -- search for names like Zubieta and Wager in PubMed) makes clear. But Orac's criticism of the makeup of the two groups, and his scrutiny of the effect size, seem like valid questions to raise about this study, which the authors admit is preliminary.
Robert Langreth Robert Langreth Treatments Front-loading bias: I love it! I think that is what some people would call a good lead, right? I guess I could have written something bland like "People disagree about Harvard placebo study". More seriously, though, I'm definitely very aware of A)Benedetti's work B) Zubieta's and Wager's work and C) your very fine article in Wired on the placebo effect. I do think that the thing that is most objectively shown thing is endogenous opioid release in response to expectation of improvement. In addition, there is definitely improvement over time, natural waxing and waning of disease. Everything else seems still seems squishy and ill-defined to me. If for example, placebo is reducing anxiety-then skip the placebo, and just have the doctor reduce the anxiety by telling them that-"if you don't have specific alarm' symptoms, back pain almost never needs to serious consequences, even though it is really annoying." I think a lot of good doctors already do this Here's an experiment someone could do to distinguish warm fuzzy feelings from having a nice doctor from pure expectation of improvement from fake treatment: Group 1: Have a doctor act like a total sexist jerk to a patient with irritable bowel syndrome, dismissing her complaints as being a female whiner and IBS not being a real disease. At the end of being really nasty, the rude doctors looks at the patient and says, however, these placebo pills have been rigorously proven in studies to reduce bowel symptoms by 50% if you take them twice a day and don't miss a dose. Then he dismissively says he has to go deal with people with more serious problems. This group is designed to have negative unpleasant feeling related to the doctor-patients relationship, but give expectation of improvement from the fake pills themselves. Group 2: The doctor is an equal jerk to the patient, and at the end gives them placebo pills saying, I don't think these will help at all, but they have no side effects so you might as well take them twice a day, you never know. This group is designed to have negative expectations about the doctor and about the fake treatment. Group 3: The doctor is really warm and nice to the patients, takes them very seriously, talks a lot a...
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