Detailed guides to painful problems, treatments & more

A failure to replicate the extraordinary result: lasting effect of open-label placebo

PainSci » bibliography » Kleine-Borgmann et al 2022
Tags: placebo, mind

One article on PainSci cites Kleine-Borgmann 2022: Placebo Power Hype

Plain white pill bottle labelled “powerful medicine.”

PainSci commentary on Kleine-Borgmann 2022: ?This page is one of thousands in the 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 wherever possible.

Back in 2019, Kleine-Borgmann et al reported that prescribing an honest placebo for back pain was more helpful than typical care. Three years later, they had important follow-up: they have now also reported that the benefit did not last, that the data “do not support the previously suggested assumption that a three-week open-label placebo treatment has long-term effects.”

Not a surprise. As the authors note, “research on non-deceptive placebos is still in its early stages, and studies on long-term effects are almost nonexistent.” They present their findings primarily in contrast to the only other data of this kind: Carvalho et al’s rather startling 2021 conclusion that the benefits of their honest placebo were sustained for five years, which got placebo fans quite overheated. Those researchers did acknowledge a major methodological limitation, but it was more pointedly described by Kleine-Borgmann et al. like so:

“…because of a predefined crossover from treatment-as-usual to open-label placebo, in which all patients received OLP at the end of the study, follow-up was performed as an observational analysis without a control group, preventing causal attribution of continued improvements to OLP treatment.”

Er, say what now? Translated: all the subjects in the Carvalho study got open-label placebo in the end, so ultimately the study was not a controlled trial, not a comparison, and so not very persuasive. Most data has some utility, but some of it has a lot less than others, and arguably there was no point in studying honest placebo this way in the first place. Carvalho’s sensational findings of super durable benefits from non-deceptive placebo never deserved to be a sensation; they were probably just an artifact.

~ Paul Ingraham

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.

Chronic low back pain is prevalent, highly disabling and a relevant socioeconomic health concern. Although allocated to placebo groups, patients in randomized controlled trials show significant pain relief, pointing to the relevance of placebo effects. Overcoming ethical and legal concerns related to deceptive placebos, recent studies have demonstrated the efficacy of short-term treatments for chronic low back pain with open-label (i.e., non-deceptive) placebos. However, data on long-term efficacy of open-label placebos are sparse. Here, we report a three-year follow-up of our previously published randomized controlled trial demonstrating pain reduction, improvement in disability and depressive symptoms after a three-week treatment with open-label placebos. Including records from N=89 previously enrolled patients, we investigated changes between the groups with and without previous open-label placebo treatment in pain intensity (primary outcome), disability and mood (secondary outcomes), biopsychosocial factors and lifestyle (exploratory outcomes) from parent baseline to follow-up. Over the three-year period, there were no differences in any outcome between groups with and without open-label placebo treatment. Therefore, our follow-up data do not support the previously suggested assumption that a three-week open-label placebo treatment has long-term effects. This study was pre-registered on April 14, 2020, in the German Clinical Trials Register (registration number DRKS00021405).

related content

Specifically regarding Kleine-Borgmann 2022:

This page is part of the PainScience BIBLIOGRAPHY, which contains plain language summaries of thousands of scientific papers & others sources. It’s like a highly specialized blog. A few highlights:

PainSci Member Login » Submit your email to unlock member content. If you can’t remember/access your registration email, please contact me. ~ Paul Ingraham, PainSci Publisher