MUC1 and Patent ductus arteriosus: Finally, 6 of the prognostic factors (Table 4) remained in the equation, PDA with the highest OR (23.34), KL-6/14d (OR = 13.59), gestational age (OR = 4.58), mechanical ventilation (OR = 4.45), antenatal steroids (OR = 0.19), and sex (female OR = 0.30).