Deceptive trial of “placebos without deception”
PainSci summary of Kaptchuk 2010?This page is one of thousands in the PainScience.com bibliography. It is not a general article: it is focused on a single scientific paper, and it may provide only just enough context for the summary to make sense. Links to other papers and more general information are provided at the bottom of the page, as often as possible. ★☆☆☆☆?1-star ratings are for negative examples, fatally flawed papers, junk science, suspected fraud. Ratings are a highly subjective opinion, and subject to revision at any time. If you think this paper has been incorrectly rated, please let me know.
If a patient is given a placebo, knowing it’s a placebo, might they still benefit and find improvement in their Irritable Bowel Syndrome? Certainly they will if they are told “this fake medicine is really awesome.” This study purports to show that placebo works even when you know it’s a placebo, i.e. without deception, and that conclusion was widely and uncritically reported. I have a different perspective: the authors greatly exaggerated the “power of placebo” to the study subjects, and thus “they did the very thing they claimed they weren’t doing” (see Dr. David Gorski’s analysis).
The lead author, Ted Kaptchuk, is transparently attempting to aggrandize placebo, to expand its definition in a way that would (just coincidentally!) make it seem more magical and awesome — thus reinforcing his own story.
original abstract†Abstracts here may not perfectly match originals, for a variety of technical and practical reasons. Some abstacts are truncated for my purposes here, if they are particularly long-winded and unhelpful. I occasionally add clarifying notes. And I make some minor corrections.
BACKGROUND: Placebo treatment can significantly influence subjective symptoms. However, it is widely believed that response to placebo requires concealment or deception. We tested whether open-label placebo (non-deceptive and non-concealed administration) is superior to a no-treatment control with matched patient-provider interactions in the treatment of irritable bowel syndrome (IBS).
METHODS: Two-group, randomized, controlled three week trial (August 2009-April 2010) conducted at a single academic center, involving 80 primarily female (70%) patients, mean age 47 ± 18 with IBS diagnosed by Rome III criteria and with a score ≥ 150 on the IBS Symptom Severity Scale (IBS-SSS). Patients were randomized to either open-label placebo pills presented as "placebo pills made of an inert substance, like sugar pills, that have been shown in clinical studies to produce significant improvement in IBS symptoms through mind-body self-healing processes" or no-treatment controls with the same quality of interaction with providers. The primary outcome was IBS Global Improvement Scale (IBS-GIS). Secondary measures were IBS Symptom Severity Scale (IBS-SSS), IBS Adequate Relief (IBS-AR) and IBS Quality of Life (IBS-QoL). FINDINGS: Open-label placebo produced significantly higher mean (±SD) global improvement scores (IBS-GIS) at both 11-day midpoint (5.2 ± 1.0 vs. 4.0 ± 1.1, p<.001) and at 21-day endpoint (5.0 ± 1.5 vs. 3.9 ± 1.3, p = .002). Significant results were also observed at both time points for reduced symptom severity (IBS-SSS, p = .008 and p = .03) and adequate relief (IBS-AR, p = .02 and p = .03); and a trend favoring open-label placebo was observed for quality of life (IBS-QoL) at the 21-day endpoint (p = .08).
CONCLUSION: Placebos administered without deception may be an effective treatment for IBS. Further research is warranted in IBS, and perhaps other conditions, to elucidate whether physicians can benefit patients using placebos consistent with informed consent.
related content
One article on PainScience.com cites Kaptchuk 2010 as a source:
- PS Placebo Power Hype — The placebo effect is fascinating, but its “power” isn’t all it’s cracked up to be
