Table 4.

Uni- and multivariable linear regression for length of stay (days)

FactorDays95% CIP
Univariable analyses
 AKI (occurrence)53.349.5 to 57.1<0.001
 AKI (stage 1 only)39.432.7 to 46.1<0.001
 AKI (no. of episodes)19.116.3 to 22.0<0.001
 Apgar (1 min)−3.6−4.9 to −2.3<0.001
 Apgar (5 min)−5.4−7.1 to −3.6<0.001
 Birth weight (100 g)−9.2−10.1 to −8.4<0.001
 CRIB II11.23.8 to 18.70.003
 Gestational age (wk)−9.4−10.3 to −8.6<0.001
 Preeclampsia−2.6−12.8 to 7.50.61
 Race (non-Caucasian)−1.7−8.9 to 5.50.64
 Sex (boys)3.3−3.7 to 10.40.36
 SGA−24.9−32.9 to −16.9<0.001
Multivariable analyses (final models)
 AKI (occurrence)11.75.1 to 18.40.001
  Birth weight (100 g)−2.9−4.8 to −1.10.002
  CRIB II1.1−0.7 to 3.00.23
  Gestational age (wk)−5.1−7.6 to −2.6<0.001
 AKI (stage 1 only)5.4−0.8 to 11.50.09
  Birth weight (100 g)−2.0−3.6 to −0.30.02
  CRIB II1.90.3 to 3.60.02
  Gestational age (wk)−5.7−7.9 to −3.6<0.001
 AKI (no. of episodes)4.92.0 to 7.70.001
  Birth weight (100 g)−3.0−4.8 to −1.10.002
  CRIB II1.4−0.5 to 3.20.15
  Gestational age (wk)−4.8−7.3 to −2.3<0.001
  • CRIB II, updated clinical risk index for babies; SGA, small for gestational age.