Cortisol level (mg/dl)

Independent t-test

Mean

SD

t

P-value

Mortality

Alive

26.97

7.34

-6.345

0.001

Died

37.51

8.31

Intraventricular hemorrhage

No

29.38

8.63

3.816

0.001

Yes

37.63

8.82

Bronchopulmonary dysplasia

No

30.45

9.14

2.174

0.032

Yes

36.39

9.00