Table 2.

Matching criteria.

Matching criteria	Matching categories
EMSa district	Study group cases and control group cases had to be from same district
Date of emergency mission	During the historical control period, the same month and calendar day was used as starting point for the backward and forward search; the first case that fulfilled the matching criteria listed below was included
Patient’s age	Same age ± 10 years
Sex	Female
	Male
Symptoms	Chest pain (typically)
	No chest pain (atypically), but other symptoms (ie, nausea, vomiting)
	No symptoms

^aEMS: emergency medical service.