Research Library
Placebo research library
A starting collection of independent sources on placebo and open-label placebo research — read the research, not the marketing. Every item links to the original publication or institution. Citation does not imply endorsement of Efficacy Labs.
Study summaries
Individual studies, read in full and summarised plainly.
Each summary covers the question the researchers asked, how the trial was run, what was reported and — always — where the evidence is thin. Every page links to the original publication.
- Add-on treatment
- Cancer survivorship
- Chronic pain
- Clinical practice
- Double-blind placebo
- Effect size
- Evidence synthesis
- Expectation
- Fatigue
- Irritable bowel syndrome
- Labelling
- Mechanisms
- Methodology
- Migraine
- Nocebo
- Non-deception
- Open-label placebo
- Skeptical evidence
Randomized controlled trial
PLoS ONE · 2010
Open-label placebo in IBS (2010)
The trial that started modern open-label placebo research: patients were openly told their pills were inert placebos, and were still assessed against a no-treatment control.
Read the summary →Randomized controlled trial
Pain · 2016
Open-label placebo in chronic low back pain (2016)
An open-label placebo added on top of patients' existing treatment as usual for chronic low back pain, tested over three weeks in Portugal.
Read the summary →Randomized controlled trial
Scientific Reports · 2018
Open-label placebo and cancer-related fatigue (2018)
Cancer survivors with persistent fatigue took openly labelled placebo pills for three weeks alongside their usual care.
Read the summary →Randomized controlled trial
Science Translational Medicine · 2014
Labelling and migraine treatment (2014)
A within-subject migraine study that mislabelled and correctly labelled both a real drug and a placebo, isolating how much of the outcome tracked the label rather than the pill.
Read the summary →Meta-analysis
Scientific Reports · 2021
Open-label placebo meta-analysis (2021)
A pooled analysis of open-label placebo trials across conditions, reporting a positive overall effect alongside significant caveats about study quality.
Read the summary →Meta-analysis
The New England Journal of Medicine · 2001
Is the placebo powerless? (2001)
The influential skeptical analysis: pooling trials with both placebo and no-treatment arms found little evidence of clinically important placebo effects outside subjective outcomes such as pain.
Read the summary →Review
The New England Journal of Medicine · 2020
Placebo and nocebo effects (2020)
A general-medicine review of proposed mechanisms behind placebo and nocebo responses, including expectation, conditioning and the clinical encounter itself.
Read the summary →Randomized controlled trial
Pain · 2021
Open-label vs double-blind placebo in IBS (2021)
The comparison the earlier trials were missing: open-label placebo tested directly against concealed double-blind placebo and against no pill.
Read the summary →
Also indexed
National Center for Complementary and Integrative Health (NIH)
Placebo Effects: What the Science Says
A public-health overview of how placebo responses are studied and what researchers currently understand about them.
Ongoing
(opens in a new tab)Scientific Reports / PubMed
Open-label placebo treatment: a systematic review and meta-analysis
A pooled analysis of trials in which participants were told they were receiving a placebo. Reported effects vary by population, outcome and methodology.
2021
(opens in a new tab)PLoS ONE / PubMed
Placebos without deception: a randomized controlled trial in IBS
An early open-label placebo trial that prompted much of the subsequent research interest in non-deceptive placebo administration.
2010
(opens in a new tab)The New England Journal of Medicine
Placebo and nocebo effects
A review article describing mechanisms researchers have proposed for placebo and nocebo responses, and the limits of current evidence.
2020
(opens in a new tab)Beth Israel Deaconess Medical Center / Harvard Medical School
Program in Placebo Studies (PiPS)
An academic research program dedicated to the study of placebo effects and the patient–clinician relationship.
Ongoing
(opens in a new tab)National Library of Medicine
PubMed: open-label placebo literature
The primary index for peer-reviewed literature on placebo and open-label placebo research.
Ongoing
(opens in a new tab)
This library is being built.
We are assembling a broader, categorised index of placebo literature — including open-label placebo trials, mechanism research, nocebo studies and methodological reviews. If you have published work you think belongs here, or you are looking for something specific, tell us.