Table 5.

Demographic and chronological factors of acute myocardial infarction (AMI) without arrest and out‐of‐hospital cardiac arrest (OHCA) with cardiac origin transported by emergency medical service (EMS) according to the number of phone calls to hospitals from ambulances

	AMI without arrest		Crude OR (95% CI)	Adjusted OR (95% CI)	OHCA with cardiac origin		Crude OR (95% CI)	Adjusted OR (95% CI)
	No. of phone calls to hospitals				No. of phone calls to hospitals
	1 (n = 7,222)	2 and over (n = 1,374)			1 (n = 6,480)	2 and over (n = 2,798)
Sex
Male	5,052	973	Reference	Reference	3,930	1,665	Reference	Reference
Female	2,170	401	0.96 (0.85–1.09)	1.05 (0.92–1.20)	2,550	1,133	1.05 (0.96–1.15)	1.06 (0.96–1.16)
Age, years
18–64	2,821	619	Reference	Reference	1,801	821	Reference	Reference
≥65	4,401	755	0.78 (0.70–0.88)	0.79 (0.70–0.90)	4,679	1,977	0.93 (0.84–1.02)	0.89 (0.80–0.99)
Witnessed status
Arrest not witnessed	—	—	—	—	3,480	1,483	Reference	Reference
Arrest witnessed by bystanders and EMS	—	—	—	—	3,000	1,315	1.03 (0.94–1.12)	1.05 (0.96–1.14)
Location
Home	5,018	964	Reference	Reference	4,436	1,999	Reference	Reference
Other location	2,204	410	0.97 (0.85–1.10)	1.03 (0.90–1.18)	2,044	799	0.87 (0.79–0.96)	0.92 (0.83–1.02)
Season
Spring and summer (April–September)	3,407	616	Reference	Reference	2,735	1,094	Reference	Reference
Autumn and winter (October–March)	3,815	758	1.10 (0.98–1.23)	1.12 (0.99–1.26)	3,745	1,704	1.14 (1.04–1.25)	1.14 (1.05–1.25)
Day of the week
Weekday (Monday–Friday)	5,231	937	Reference	Reference	4,753	1,953	Reference	Reference
Weekend (Saturday–Sunday)	1,991	437	1.23 (1.08–1.34)	1.24 (1.09–1.40)	1,727	845	1.19 (1.08–1.31)	1.19 (1.08–1.30)
Time of day
9.00 am–5.00 pm	2,882	389	Reference	Reference	2,537	824	Reference	Reference
5.00 pm–9.00 am	4,340	985	1.68 (1.48–1.91)	1.67 (1.47–1.90)	3,943	1,974	1.54 (1.40–1.70)	1.52 (1.38–1.68)

—, not applicable; CI, confidence interval; OR, odds ratio.