Science
Rooted in more than a decade of open-label placebo research.
Open-label placebo spans randomized trials, systematic reviews, and expectancy research. Rxpect is testing whether those transparent mechanisms survive the move to software.
0.72
Pooled effect size (SMD) of OLP vs. no treatment
von Wernsdorff et al., 2021
13%
of U.S. adults live with chronic low back pain
AAFP, 2024
8.2%
of U.S. adults have chronic severe back pain
NCCIH national survey
Systematic evidence
Reviews and meta-analyses testing whether open-label placebo effects hold across clinical settings.
Scientific Reports · von Wernsdorff et al. · 202113 trials · SMD 0.72
Effects of open-label placebos in clinical trials: a systematic review and meta-analysis
Meta-analysis of clinical OLP trials across back pain, IBS, depression, allergic rhinitis, and more. Found a significant overall effect of OLP compared with no treatment.
Scientific Reports · network meta-analysis · 202325 clinical trials
The roles of expectation, comparator, administration route, and population in open-label placebo effects
OLP effects vary with expectation, comparator, administration route, and population, which bears directly on how a digital rationale and ritual should be designed.
Open-label placebo trials
Randomized trials where patients were told plainly they were taking a placebo, and still reported improvement.
Pain · Carvalho et al. · 2016Chronic low back pain
Open-label placebo treatment in chronic low back pain: a randomized controlled trial
Adults with chronic low back pain received OLP with an honest rationale or treatment as usual. The OLP group reported greater reductions in pain and disability over three weeks.
PLoS ONE · Kaptchuk et al. · 2010First OLP RCT
Placebos without deception: a randomized controlled trial in irritable bowel syndrome
The first randomized trial of open-label placebo. Patients knew the pills were inert and still reported greater global improvement than no-treatment controls.
BMJ · Kaptchuk & Miller · 2018Multi-condition review
Open label placebo: can honestly prescribed placebos evoke meaningful therapeutic benefits?
Review of OLP evidence across chronic pain, IBS, depression, and allergic rhinitis, concluding that transparency does not eliminate placebo mechanisms.
Pain Medicine · Carvalho et al. · 2020Long-term follow-up
Open-label placebo for chronic low back pain: a 5-year follow-up
Five-year follow-up of participants from an OLP trial in chronic low back pain.
Rationale & expectancy
How the explanation a patient hears, and the ritual they follow, shape the response. These are the levers Rxpect builds on.
Science Translational Medicine · Kam-Hansen et al. · 2014Labeling shaped response
Altered placebo and drug labeling changes the outcome of episodic migraine attacks
Treatment information and the pill-taking ritual changed migraine outcomes, supporting rationale and expectation as active ingredients.
J Pain · Bernstein et al. · 2021Patient acceptance
Treating pain with open-label placebos: a qualitative study with post-surgical pain patients
Patients accepted OLP when the rationale was honest and positive, pointing to rationale and transparency as active ingredients.
Registered studies
Independent academic studies on ClinicalTrials.gov, listed for field context.
ClinicalTrials.gov · third-party academic study · Registry
Open-label Placebo for Chronic Low Back Pain (NCT06931158)
Independent remote randomized study of OLP rationales in chronic low back pain.
ClinicalTrials.gov · completed academic study · Registry
Open-label Placebo for Chronic Low Back Pain (NCT03639750)
Earlier completed OLP study in chronic low back pain.
References to third-party research, investigators, or institutions describe published literature for scientific context only. They do not imply endorsement, partnership, or affiliation unless separately disclosed.
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