Evidence map›Paper›PMID 36380220›Full record

Trial reportNeuropsychopharmacology : official publication of the American College of Neuropsychopharmacology2023

Does cannabidiol make cannabis safer? A randomised, double-blind, cross-over trial of cannabis with four different CBD:THC ratios.

Amir Englund, Dominic Oliver, Edward Chesney, Lucy Chester, Jack Wilson, Simina Sovi, Andrea De Micheli, John Hodsoll, Paolo Fusar-Poli, John Strang and 3 more

Open access · hybridAbstract readRandomized Controlled Trial
PubMed Full text at PMC Publisher
In one paragraph

Trial report in Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology, 2023. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 48 papers, 7 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
48citing papers in PubMed, 7 pooled it
13.9field-weighted citation impact, top 1% of its field
1 · What the graph read from 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.

2 · The registry

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.

3 · Its place in the literature

Who cites it

48 citing papers in PubMed, 7 syntheses or guidelines pooled it, 88 citations in OpenAlex.

  1. Pooled it
  2. Pooled it
  3. Pooled it
  4. Pooled it
  5. Does acute cannabidiol (CBD) use impair performance? A meta-analysis and comparison with placebo and delta-9-tetrahydrocannabinol (THC).Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 2024
    Pooled it
  6. Pooled it
  7. Pooled it
  8. Does cannabidiol reduce the adverse effects of cannabis in schizophrenia? A randomised, double-blind, cross-over trial.Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 2025
    Trial
  9. Acute effects of different types of cannabis on young adult and adolescent resting-state brain networks.Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 2024
    Trial
  10. Trial
  11. Trial
  12. Trial
  13. Trial
  14. Effect of CannEpilJournal of psychopharmacology (Oxford, England) · 2023
    Trial
  15. Longitudinal neurocognitive trajectories in a large cohort of youth who use cannabis: combining self-report and toxicology.Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 2026
    Article
  16. Article
  17. Article
  18. Article
  19. Article
  20. Article
4 · The record

Corrections and comments

5 · Who and what money

Authors and funding

13 authors at 3 institutions in 3 countries.

Amir EnglundNational Addiction Centre, Institute of Psychiatry, Psychology and Neuroscience, King's College London, 4 Windsor Walk, SE5 8AF, London, UK. Amir.englund@kcl.ac.uk.ORCID 0000-0002-2478-209X
Dominic OliverDepartment of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, 16 De Crespigny Park, SE5 8AF, London, UK.ORCID 0000-0002-8920-3407
Edward ChesneyDepartment of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, 16 De Crespigny Park, SE5 8AF, London, UK.ORCID 0000-0003-2851-5252
Lucy ChesterDepartment of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, 16 De Crespigny Park, SE5 8AF, London, UK.
Jack WilsonThe Matilda Centre for Research in Mental Health and Substance Use, The University of Sydney, Level 6, Jane Foss Russell Building, G02, Sydney, 2006, NSW, Australia.ORCID 0000-0002-2732-1731
Simina SoviDepartment of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, 16 De Crespigny Park, SE5 8AF, London, UK.
Andrea De MicheliDepartment of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, 16 De Crespigny Park, SE5 8AF, London, UK.
John HodsollDepartment of Biostatistics and Health Informatics, Institute of Psychiatry, Psychology and Neuroscience, King's College London, 16 De Crespigny Park, SE5 8AF, London, UK.
Paolo Fusar-PoliDepartment of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, 16 De Crespigny Park, SE5 8AF, London, UK.
John StrangNational Addiction Centre, Institute of Psychiatry, Psychology and Neuroscience, King's College London, 4 Windsor Walk, SE5 8AF, London, UK.
Robin M MurrayDepartment of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, 16 De Crespigny Park, SE5 8AF, London, UK.ORCID 0000-0003-0829-0519
Tom P FreemanDepartment of Psychology, University of Bath, Claverton Down, Bath, BA2 7AY, UK.
Philip McGuireDepartment of Psychosis Studies, Institute of Psychiatry, Psychology and Neuroscience, King's College London, 16 De Crespigny Park, SE5 8AF, London, UK.ORCID 0000-0003-4381-0532
King's College London · GBThe University of Sydney · AUUniversity of Bath · GB

Funding

Medical Research Council MR/P006841/1Wellcome Trust
6 · The paper itself

Abstract

As countries adopt more permissive cannabis policies, it is increasingly important to identify strategies that can reduce the harmful effects of cannabis use. This study aimed to determine if increasing the CBD content of cannabis can reduce its harmful effects. Forty-six healthy, infrequent cannabis users participated in a double-blind, within-subject, randomised trial of cannabis preparations varying in CBD content. There was an initial baseline visit followed by four drug administration visits, in which participants inhaled vaporised cannabis containing 10 mg THC and either 0 mg (0:1 CBD:THC), 10 mg (1:1), 20 mg (2:1), or 30 mg (3:1) CBD, in a randomised, counter-balanced order. The primary outcome was change in delayed verbal recall on the Hopkins Verbal Learning Task. Secondary outcomes included change in severity of psychotic symptoms (e.g., Positive and Negative Syndrome Scale [PANSS] positive subscale), plus further cognitive, subjective, pleasurable, pharmacological and physiological effects. Serial plasma concentrations of THC and CBD were measured. THC (0:1) was associated with impaired delayed verbal recall (t(45) = 3.399, d = 0.50, p = 0.001) and induced positive psychotic symptoms on the PANSS (t(45) = -4.709, d = 0.69, p = 2.41 × 10

Indexed as

CannabidiolCannabisHallucinogensCannabinoid Receptor AgonistsCross-Over StudiesDouble-Blind MethodDronabinolHumansCannabidiolCannabinoid Receptor AgonistsDronabinolHallucinogens

Identifiers

PMID36380220
PMCPMC10156730
OpenAlexW4309100871

What OpenQuestion holds

Textmetadata
LicenceCC BY
Read underepoch 390

Registered trials

None linked

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.