TABLE 3.

MODEL PREDICTION C STATISTIC (AKIN TO AREA UNDER THE RECEIVER–OPERATING CHARACTERISTIC CURVE) AND INDIVIDUAL VARIABLES FOR DAYS 1–28 MODELS FOR THE DEVELOPMENT COHORT*

Day 1		Day 3		Day 7
Variable	C Statistic	Variable	C Statistic	Variable	C Statistic
Gestational age	0.750	Gestational age	0.745	Respiratory support	0.771
Birth weight	0.772	Respiratory support	0.787	Gestational age	0.806
FiO2	0.784	Birth weight	0.798	Birth weight	0.814
Respiratory support	0.790	FiO2	0.805	FiO2	0.817
Race and ethnicity	0.791	Male sex	0.807	Race and ethnicity	0.817
Male sex	0.793	Race and ethnicity	0.807	Male sex	0.818
Day 14		Day 21		Day 28
Variable	C Statistic	Variable	C Statistic	Variable	C Statistic
Respiratory support	0.795	Respiratory support	0.802	Respiratory support	0.823
Birth weight	0.819	FiO2	0.831	FiO2	0.852
Gestational age	0.825	Gestational age	0.833	Birth weight	0.851
FiO2	0.826	Birth weight	0.835	Race and ethnicity	0.853
Race and ethnicity	0.826	Race and ethnicity	0.835	Gestational age	0.853
Male sex	0.827	Male sex	0.836	Male sex	0.854

^*For example, on Day 7, respiratory support provides 77.1% of the predictive ability of the C statistic, with a small incremental increase in the C statistic with additional variables to a final model C statistic of 81.8%.