Table 2.

Results of the stepwise multivariate logistic regression analysis

Coefficients	β coefficient	Odds ratio	95% CI	P-value
Intercept	-2.7717	0.06	(0.02—0.19)	< 0.01
Age
< 43 years	0			reference
43–67 years	-1.024	0.36	(0.17—0.78)	< 0.01
≥ 67 years	-2.4262	0.09	(0.04—0.22)	< 0.01
Etiology
Internal
Cardiac	0			reference
Respiratory	1.5243	4.59	(1.71—12.3)	< 0.01
Cerebrovascular	2.1272	8.39	(3.47—20.3)	< 0.01
External	1.2052	3.34	(1.57—7.1)	< 0.01
Unknown	0.7364	2.09	(0.71—6.19)	0.18
Low-flow time
< 20 min	0			reference
≥ 20 min	1.7976	6.03	(2.18—16.7)	< 0.01
< 6.62	0			reference
pH
6.62–7.06	0.6964	2.01	(0.74—5.44)	0.17
≥ 7.06	-0.1774	0.84	(0.27—2.6)	0.76

Low-flow time means the time from the initiation of chest compressions to the return of spontaneous circulation