Who is the Cohort?
Cases are people included in the Cohort who had a drug-related overdose since January 1, 2015. This period was the beginning of the rapid rise in illicit drug overdoses and deaths in B.C.
- Administration of the opioid antagonist naloxone by paramedics
- A call to the Drug and Poison Information Center about an opioid-related event
- Physician-diagnosed opioid overdose at an emergency department
- Coroner-determined illicit drug toxicity death
- A visit to a hospital, emergency department, or physician with an associated overdose diagnosis code
- Vital Statistics overdose-related death.
Overdose events can show up in several datasets. For example, an overdose record may be in ambulance, emergency, and hospital datasets. These events are grouped to prevent over-counting of overdoses.
Controls are people used as a comparison group for the Cohort. The Control group is selected from a 20% random sample of the B.C. population. Like cases, health and prescribing histories are available for this group.
A matched control group is also available. Previous Cohort analyses have matched people on birth year, sex, and Local Health Area of residence.