Impact of an emergency medical dispatch system on survival from out-of-hospital cardiac arrest: a population-based study

Table 4 Stratum-specific estimate of the association between the dispatch centre system and telephone number dialled and survival outcome at 30 days

	30-day survival adjusted OR (95 % CI)^a	p-value
FD telephone number 1–8 dialled first compared to EMS telephone number 1–5 dialled first
In the multiple dispatch centre system (i.e., FD dispatch centre alone vs. EMS dispatch centre alone)	0.44 (0.32–0.63)^b	0.001
In the single dispatch centre system	0.81 (0.53–1.22)^b	0.314
Single dispatch centre system compared to the multiple dispatch centre system
When EMS telephone number 1–5 is dialled first (i.e., single dispatch centre vs. EMS dispatch centre alone)	1.24 (0.84–2.21)^c	0.270
When FD telephone number 1–8 is dialled first (i.e., single dispatch centre vs. FD dispatch centre alone)	2.25 (1.56–3.24)^c	<0.001

EMS emergency medical service, FD fire department, OR odds ratio, CI confidence interval; cath lab: catheterization laboratory
^aUnconditional logistic regression adjusted for covariates at the first call (ventricular fibrillation, age, sex, place of cardiac arrest, witness to collapse, first call to FD telephone number, period of cardiac arrest [2005–2010 and 2011–2013], cath lab first admission) (n = 6866). Logistic regression = 1672; p <0.001; R2 = 0.48; area under the curve = 0.92; 95 % CI, 0.91–0.94
^bIndicates OR for FD phone number compared to EMS phone number (reference OR = 1.00)
^cIndicates OR for single dispatch compared to the multiple dispatch centre (reference OR = 1.00)

ISSN: 1757-7241