Evidence map›Paper›PMID 26903403›Full record

ArticleBiological psychiatry2016

Changes in Cannabis Potency Over the Last 2 Decades (1995-2014): Analysis of Current Data in the United States.

Mahmoud A ElSohly, Zlatko Mehmedic, Susan Foster, Chandrani Gon, Suman Chandra, James C Church

Open access · greenAbstract read
PubMed Full text at PMC Publisher
In one paragraph

Article in Biological psychiatry, 2016. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 452 papers, 7 of them syntheses that pooled it.

0numbers the graph read from it
0cells of the map it votes in
452citing papers in PubMed, 7 pooled it
97.9field-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

452 citing papers in PubMed, 7 syntheses or guidelines pooled it, 980 citations in OpenAlex.

  1. Pooled it
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  8. CBClinical pharmacology and therapeutics · 2025
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  13. The role of subcortical brain tissue iron as an indicator of dopamine neurophysiology in adolescent cannabis use.Neuropsychopharmacology : official publication of the American College of Neuropsychopharmacology · 2026
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392 more citing papers are in PubMed but not listed here.

4 · The record

Corrections and comments

5 · Who and what money

Authors and funding

6 authors at 2 institutions in 1 country.

Mahmoud A ElSohlyNational Center for Natural Products Research, School of Pharmacy, University of Mississippi, University, Mississippi. Electronic address: melsohly@olemiss.edu.
Zlatko MehmedicNational Center for Natural Products Research, School of Pharmacy, University of Mississippi, University, Mississippi.
Susan FosterNational Center for Natural Products Research, School of Pharmacy, University of Mississippi, University, Mississippi.
Chandrani GonNational Center for Natural Products Research, School of Pharmacy, University of Mississippi, University, Mississippi.
Suman ChandraNational Center for Natural Products Research, School of Pharmacy, University of Mississippi, University, Mississippi.
James C ChurchDepartment of Computer Science, University of West Georgia, Carrollton, Georgia.
University of Mississippi · USUniversity of West Georgia · US

Funding

PRODUCTION ANALYSIS &DISTRIBUTION CANNABIS &MARIJUANAN01DA007707 · NIDA · UNIVERSITY OF MISSISSIPPI · PI ELSOHLY, MAHMOUD A · 2000 to 2000
$1.1M
NIDA NIH HHS N01 DA007707NIDA NIH HHS N01DA-10-7773
6 · The paper itself

Abstract

backgroundMarijuana is the most widely used illicit drug in the United States and all over the world. Reports indicate that the potency of cannabis preparation has been increasing. This report examines the concentration of cannabinoids in illicit cannabis products seized by the U.S. Drug Enforcement Administration over the last 2 decades, with particular emphasis on Δ(9)-tetrahydrocannabinol and cannabidiol.

methodsSamples in this report were received over time from materials confiscated by the Drug Enforcement Administration and processed for analysis using a validated gas chromatography with flame ionization detector method.

resultsBetween January 1, 1995, and December 31, 2014, 38,681 samples of cannabis preparations were received and analyzed. The data showed that although the number of marijuana samples seized over the last 4 years has declined, the number of sinsemilla samples has increased. Overall, the potency of illicit cannabis plant material has consistently increased over time since 1995 from ~4% in 1995 to ~12% in 2014. The cannabidiol content has decreased on average from ~.28% in 2001 to <.15% in 2014, resulting in a change in the ratio of Δ(9)-tetrahydrocannabinol to cannabidiol from 14 times in 1995 to ~80 times in 2014.

conclusionsThere is a shift in the production of illicit cannabis plant material from regular marijuana to sinsemilla. This increase in potency poses higher risk of cannabis use, particularly among adolescents.

Indexed as

CannabinoidsCannabisChromatography, GasHumansIllicit DrugsSubstance Abuse DetectionUnited StatesCannabinoidsIllicit DrugsCannabinoidsCannabis sativaCBDGas chromatography with flame ionization detectorPotencyΔ(9)-THC

Identifiers

PMID26903403
PMCPMC4987131
OpenAlexW2253496291

What OpenQuestion holds

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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.