Equations Selected variables Equation
Equation 1 All the collected variables EQ1=2,32-(0,44*GENDER)- (0,29*Adequacy)+(0,37*Hypertension)-(0,11*Smoking)-(0,48*Chorio)-(0,53*Antenatal_cortic)+ (0,02*SURF)-(0,57*RespSupp14th_0)-(0,87*RespSupp14th_1e2)-(0,3*PDA)-(0,00035*NEC_uptothe14th)+(0,02*EARLYSEPSIS)-(0,1*LATESEPSIS)-(0,0009*GAdays)-(0,0044*WEIGHT_g)+(0,05*FiO214th)
Equation 2 Chorioamnionitis, gestational age, birth weight, gender, need for surfactant, patent ductus arteriosus, late sepsis up to the 14th day of life, fio2 and respiratory support on the 14th day of life (variables whose p-value of Fisher’s exact test was less than 5% in a univariate analysis) EQ2=3,47-(0,36*GENDER)-(0,55*Chorio)+(0,17*SURF)-(0,63*RespSupp14th_0)-(0,91*RespSupp14th_1e2)-(0,33*PDA)+(0,034*LATESEPSIS)-(0,011*GAdays)-(0,0029*WEIGHT_g)+(0,058* FiO214th)
Equation 3 Gestational age, gender, fio2 and respiratory support on the 14th day of life (using the stepwise computational selection method) EQ3=8,74-(0,3*GENDER)-(0,68*RespSupp14th_0)-(0,97*RespSupp14th_1e2)-(0,0532* GAdays) +(0,05* FiO214th)
Equation 4 Gender, patent ductus arteriosus and respiratory support on the 14th day of life (using a conditional inference tree) EQ4=0,11-(0,36*GENDER)-(0,73*RespSupp14th_0)-(1,66* RespSupp14th_1e2)-(0,5*PDA)
NICHD calculator for BPD Birth weight, gestational age, gender, respiratory support on the 14th day of life (https://neonatal.rti.org/)