Emergency department visits during the 4/20 cannabis celebration
Bibliographic record
Abstract
BACKGROUND: Annual '4/20' cannabis festivals occur around the world on April 20 and often feature synchronised consumption of cannabis at 4:20 pm. The relationship between these events and demand for emergency medical services has not been systematically studied. METHODS: We conducted a population-based retrospective cohort study in Vancouver, Canada, using 10 consecutive years of data (2009-2018) from six regional hospitals. The number of emergency department (ED) visits between 4:20 pm and 11:59 pm on April 20 were compared with the number of visits during identical time intervals on control days 1 week earlier and 1 week later (ie, April 13 and April 27) using negative binomial regression. RESULTS: A total of 3468 ED visits occurred on April 20 and 6524 ED visits occurred on control days. A non-significant increase in all-cause ED visits was observed on April 20 (adjusted relative risk: 1.06; 95% CI 1.00 to 1.12). April 20 was associated with a significant increase in ED visits among prespecified subgroups including a 5-fold increase in visits for substance misuse and a 10-fold increase in visits for intoxication. The hospital closest to the festival site experienced a clinically and statistically significant 17% (95% CI 5.1% to 29.6%) relative increase in ED visits on April 20 compared with control days. INTERPRETATION: Substance use at annual '4/20' festivals may be associated with an increase in ED visits among key subgroups and at nearby hospitals. These findings may inform harm reduction initiatives and festival medical care service planning.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.188 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one teacher head, not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".