TABLE 3

Multivariate Predictors of TSB Level Reaching Exchange Transfusion Level Within 48 Hours

VariableOR (95% CI)P
Male gender1.53 (1.12–2.11).008
Gestational age, wk
    358.37 (3.38–20.69)<.001
    3611.77 (6.95–19.94)<.001
    377.29 (4.57–11.62)<.001
    383.09 (1.64–5.83).001
    391.44 (0.78–2.63).24
    40Ref
    ≥410.72 (0.35–1.47).36
Birth weight, per kg1.34 (0.97–1.83).07
Age at qualifying TSB level, h
    <241.93 (1.32–2.82)<.001
    24 to <48Ref
    48 to <720.30 (0.17–0.51)<.001
    72 to <960.14 (0.08–0.25)<.001
    ≥960.14 (0.07–0.28)<.001
TSB minus AAP phototherapy threshold, mg/dL
    −3 to less than −20.06 (0.02–0.14)<.001
    −2 to less than −10.25 (0.09–0.64).004
    −1 to <00.55 (0.30–1.00).05
    0 to <1Ref
    1 to <23.17 (1.97–5.09)<.001
    2 to <37.35 (5.08–10.63)<.001
DAT positive (if no phototherapy)2.16 (1.18–3.94).01
Home phototherapy within 1 d0.29 (0.03–3.15).31
Hospital phototherapy within 8 h
    If DAT negative or missing0.16 (0.07–0.34)<.001
Interaction DAT positive and phototherapy3.46 (1.38–8.69)a.01
  • Ref indicates reference group for OR; TSB indicates total serum bilirubin.

  • a The OR of 3.46 for the interaction term means the estimated OR for phototherapy when the DAT is positive is 3.46 times higher than when the DAT is negative, that is, 0.158 × 3.46 = 0.547 (95% CI: 0.21–1.45).