SynthesisJournal of psychopharmacology (Oxford, England)2023
Risk of bias in randomized clinical trials on psychedelic medicine: A systematic review.
Synthesis in Journal of psychopharmacology (Oxford, England), 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 25 papers, 3 of them syntheses that pooled it.
What it found
Each row is one number read from the abstract, on the scale the paper reported it, with its interval. Left of the dashed line favours the treatment, right favours the comparator. Under each row is the sentence it came from. New to these charts? A ten-minute tutorial.
The abstract states no effect estimate the extractor could read, or names no intervention and outcome on the map, so this paper lights no cell and moves no belief. It is still indexed, cited and linked below.
The trial behind it
Trials whose registry record cites this paper, or whose number appears in the abstract. A trial that started after this paper was published is citing it as background, not reporting it.
Neither the registry nor the abstract names a trial number. If this is a trial report, that itself is worth knowing.
Who cites it
25 citing papers in PubMed, 3 syntheses or guidelines pooled it, 49 citations in OpenAlex.
- The effects of psilocybin on psychological distress in cancer patients: a systematic review and meta-analysis.BMC psychology · 2026Pooled it
- Incremental efficacy systematic review and meta-analysis of psilocybin-for-depression RCTs.Psychopharmacology · 2025Pooled it
- Psychedelic-assisted therapy for treating anxiety, depression, and existential distress in people with life-threatening diseases.The Cochrane database of systematic reviews · 2024Pooled it
- Mixed-methods analysis on psychedelic-augmented meditation experiences from a randomized controlled mindfulness retreat.Scientific reports · 2026Trial
- Negative affective bias in depression following treatment with psilocybin or escitalopram - a secondary analysis from a randomized trial.Translational psychiatry · 2025Trial
- Real-World Psilocybin Therapy for Treatment-Resistant Depression: A Retrospective Observational Study.The Lancet regional health. Europe · 2026Article
- Challenges with clinical trial participants in studies with classical psychedelics: A position statement from the National Network of Depression Centers' task group on psychedelics and related compounds.Journal of psychopharmacology (Oxford, England) · 2026Article
- Landscape analysis of pre-registered clinical trials involving classical psychedelics.Journal of psychopharmacology (Oxford, England) · 2026Review
- Psilocybin in Neuropsychiatric Disorders: Seeking Valuable Evidence in History, Pure Science, Clinical Trials and Real-World Data (RWD).Brain sciences · 2026Review
- Predictors of the Effectiveness of Psychedelics in Treating Depression-A Scoping Review.International journal of molecular sciences · 2026Article
- Level of preparedness to use psilocybin among individuals seeking psychedelic risk reduction: a retrospective study of a pilot psychiatric consultation service.Frontiers in public health · 2026Article
- Ritual to relief: ethical frontiers in repurposing psychoactive substances.CNS spectrums · 2025Review
- Psilocybin-assisted Existential, Attachment and RelationaL (PEARL) therapy for patients with advanced cancer: protocol for a multi-method feasibility trial.Pilot and feasibility studies · 2025Article
- History, Hype, and Responsible Psychedelic Medicine: A Qualitative Study of Psychedelic Researchers.Journal of bioethical inquiry · 2025Article
- The Psychedelic Renaissance: A Catholic Perspective.The Linacre quarterly · 2025Article
- From Efficacy to Effectiveness: Evaluating Psychedelic Randomized Controlled Trials for Trustworthy Evidence-Based Policy and Practice.Pharmacology research & perspectives · 2025Review
- Review
- Psychedelics: Safety and Efficacy.International journal of environmental research and public health · 2025Review
- From taboo to treatment: The emergence of psychedelics in the management of pain and opioid use disorder.British journal of clinical pharmacology · 2024Review
- Psychedelics and the treatment of eating disorders: considerations for future research and practice.Journal of eating disorders · 2024Article
Corrections and comments
PubMed lists nothing against this paper. Absence here is not a guarantee, only a check that was made.
Authors and funding
4 authors at 3 institutions in 1 country.
Funding
No grant is acknowledged in the PubMed record.
Abstract
backgroundThe classical psychedelics, psilocybin, peyote, ayahuasca/
methodsWe performed a systematic literature search to identify all clinical trials on classical psychedelics with patient populations to examine descriptive data and determine the risk of bias. Two independent reviewers searched three databases (PubMed, Embase, and APA PsycNet) and extracted information on study design, study population, use of active or inactive placebo, dropouts, evaluation of blinding of intervention, and reporting of expectancy and therapeutic alliance.
resultsWe included 10 papers reporting on 10 unique trials. The trials generally included populations that were predominantly white and highly educated. The trials had small samples and considerable dropout. Blinding was either unsuccessful or not reported regardless of type of placebo. Few trials published protocols, statistical analysis plans (SAPs), and outcomes relating to psychotherapy fidelity. All trials but one were rated as high risk of bias.
conclusionSuccessful blinding of intervention is a significant challenge in this field. To better accommodate this, we suggest that future trials use a parallel-group design and utilize an active placebo on a psychedelic-naïve population. Future trials should publish trial protocol and SAPs, use clinician-rated outcomes accessed by a blinded rater, evaluate blinding of intervention, and consider measuring expectancy and therapeutic fidelity.
Indexed as
Identifiers
What OpenQuestion holds
Registered trials
Read under generation 80e0d062 · epoch 390. Bibliography from PubMed, PubMed Central and OpenAlex; grants from NIH RePORTER; trial links from ClinicalTrials.gov; estimates, votes and beliefs from the OpenQuestion graph.