Table 1.

Covariates Selected for Inclusion in Prognostic Models

Covariate	Model 1	Model 2	Model 3
Age, years			X
Discharge disposition
Discharge Disability Rating Scale (range, 0–30)			X
Discharge Glasgow Outcome Scale Extended (range, 1–8)	X	X	X
Length of hospital stay, days		X	X
Injury Severity Score (range, 0–75)
Maximum head Abbreviated Injury Severity score (range, 0–6)
Number of days alive out of ICU through day 28			X
Sex
C-statistic (95% bootstrap confidence interval)	0.882 (0.854, 0.907)	0.910 (0.883, 0.934)	0.912 (0.886, 0.937)
le Cessie–van Houwelingen p value	0.22	0.85	0.03

ICU, intensive care unit.