date of birth (admission)
date of death or discharge
lowest pH in first 4 days of life
platelet count
birth weight
gestational age
multiple gestation
duration of labor
mother treated with MgSO4
mother treated with beta-methasone
tocolysis - mother treated with beta-adrenergic drug
apgar at one minute
assisted ventilation used
pneumothorax occurred
patent ductus arteriosus detected
on suppl. oxygen at 30 days
Year of birth (+ fraction)