ArticleAmerican journal of epidemiology2022
Time-Series Analysis of Fentanyl Concentration in the Unregulated Opioid Drug Supply in a Canadian Setting.
Article in American journal of epidemiology, 2022. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 26 papers, 1 of them a synthesis 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
26 citing papers in PubMed, 1 synthesis or guideline pooled it, 48 citations in OpenAlex.
- Drug checking services for people who use drugs: a systematic review.Addiction (Abingdon, England) · 2022Pooled it
- Fentanyl purity and overdose decline: A reexamination of geographic trends.Science advances · 2026Article
- Higher prevalence of non-fatal overdose with opioid and stimulant use compared to use of opioids alone.Drug and alcohol dependence · 2026Article
- Drug sellers' use of a drug checking service amid the overdose crisis in British Columbia, Canada.Addiction (Abingdon, England) · 2026Article
- Fentanyl Purity and Overdose Decline: A Reexamination of Geographic Trends.medRxiv : the preprint server for health sciences · 2026Article
- Temporal and regional associations between fentanyl concentrations in the unregulated drug supply and drug-related mortality in British Columbia, Canada.The International journal on drug policy · 2026Article
- Development and validation of a fentanyl quantification model for drug checking services.Drug and alcohol dependence reports · 2026Article
- How population-level drug supply data are integrated into health outcomes research: a scoping review.Epidemiologic reviews · 2026Article
- Use of clinic- and community-based overdose prevention services by sex workers who use drugs: findings from a community-based cohort in Vancouver, Canada (2017-2024).Harm reduction journal · 2026Article
- High variation in purity of consumer-level illicit fentanyl samples in Los Angeles, September 2023-April 2025.The International journal on drug policy · 2025Article
- Impact of having a regular drug dealer on obtaining drug checking results consistent with expectations during a drug toxicity crisis in a Canadian setting.Drug and alcohol dependence · 2025Article
- Multidisciplinary Guidance to Care for Persons With Xylazine-Associated Wounds.Open forum infectious diseases · 2025Review
- The Police Opioid Seizure Temporal Risk (POSTeR) model of increased exposure to fatal overdose.The International journal on drug policy · 2025Article
- Navigating new norms: Addiction specialists' perspectives on opioid use disorder treatments and policy challenges in the fentanyl era.The American journal on addictions · 2025Article
- Unpacking the Effects of Decriminalization: Understanding Drug Use Experiences and Risks among Individuals Who Use Drugs in British Columbia.Harm reduction journal · 2024Article
- Fentanyl, carfentanil and other fentanyl analogues in Canada's illicit opioid supply: A cross-sectional study.Drug and alcohol dependence reports · 2024Article
- Beyond a spec: assessing heterogeneity in the unregulated opioid supply.Harm reduction journal · 2024Article
- Full Characterisation of Heroin Samples Using Infrared Spectroscopy and Multivariate Calibration.Molecules (Basel, Switzerland) · 2024Article
- 'Drug decriminalization' in Canada: a plea for a nuanced, evidence-informed, and realistic approach towards improved health outcomes.Canadian journal of public health = Revue canadienne de sante publique · 2023Article
- What impact did the COVID-19 pandemic have on the variability of fentanyl concentrations in the Vancouver, Canada illicit drug supply? An interrupted time-series analysis.BMJ public health · 2023Article
Corrections and comments
- Commented on by
- Commented on by
Authors and funding
9 authors.
Funding
No grant is acknowledged in the PubMed record.
Abstract
North America has been contending with an unregulated street drug supply in which opioids are often adulterated with illicitly manufactured fentanyl. The unpredictability of composition may result in an increased risk of overdose due to unexpected elevated concentrations of the high-potency drug. Using data from a community-based drug-checking project, we evaluated trends in fentanyl concentration of illicit opioids in the context of an overdose epidemic. Using a quantification model for fentanyl hydrochloride, historical Fourier-transform infrared spectra from opioid drug-checking samples were analyzed to determine fentanyl concentrations. Median monthly fentanyl concentrations were plotted, and polynomial and autoregressive time-series analyses were performed to examine trends over time. A total of 3,621 fentanyl-positive samples were included in the study, spanning November 2017 to December 2019. Monthly median fentanyl concentrations ranged from 4.5% to 10.4%. Time-series analyses indicated that a third-degree polynomial model fit the data well (R2 = 0.639), suggesting a cyclical pattern in median concentration over time. Notably, absolute variance in fentanyl concentration decreased by an average 0.1% per month (P < 0.001). Future research should explore the relationship between fentanyl concentration and overdose to identify potential targeted harm-reduction interventions that can respond to changes in observed fentanyl concentration.
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.