Table 4.

Cox model for predicting survival

Consideration		Risk Ratio	95% CI	p-value
Classes of mechanical ventilation	GCS at hospital administration	0.79	0.66 to 0.95	0.012
	APACHE II at hospital admission	1.12	1.00 to 1.26	0.049
	Duration of mechanical ventilation (categorical)	2.45	1.36 to 4.43	0.003
Number of days on mechanical ventilation	GCS at hospital admission	0.80	0.66 to 097	0.024
	APACHE II at hospital admission	1.12	1.00 to 1.24	0.050
	Duration of mechanical ventilation (days)	1.07	1.01 to 1.15	0.046