TABLE 1

Demographic and Clinical Characteristics of the Study Subjects

Confirmed InfectionNo Confirmed InfectionInfection Risk per 1000Bivariate Odds RatioP
Entire study, n24567 3783.6
Maternal characteristics
    Age, mean ± SD, y29.7 ± 6.629.8 ± 6.1.8
    Race, n
        White119331123.61.00
        Black2065303.10.85.51
        Asian4193984.31.21.29
        Hispanic54139843.81.07.66
        Other/unknown1143542.50.70.26
    Delivery, n
        Vaginal151469823.11.00
        Cesarean94203834.61.43.006
Newborn characteristics
    Year of birth, n
        1993–199776134135.62.75<.001
        1998–2002109248554.42.13<.001
        2003–200760291102.11.00
    Hospital/health care system of birth, n
        KPMCP164472143.51.00
        BWH81201644.01.07.29
    Gender, n
        Female108299883.61.00
        Male137373903.71.02.89
    Gestational age, mean ± SD, wk38.8 ± 1.938.7 ± 2.0
        34 to <37 wk, n29113642.50.67.05
        37 to <39 wk, n54132604.11.07.65
        ≥39 wk, n162427543.81.00
    Birth weight, mean ± SD, kg3.43 ±.563.34 ± .65.05
    5-minute Apgar score, n
        <733238913.67.67<.001
        7–10212649893.31.00
    Age at CBC paired with blood count, n
        <1 h64101506.32.29<.001
        1 to <4 h91329922.81.00
        4 to <8 h55132164.11.51.02
        8 to <24 h1973072.60.94.82
        24 to <48 h1428374.91.79.04
        ≥48 h28762.30.83.79
  • Totals in the “confirmed infection” and “no confirmed infection” columns by demographic and clinical characteristics do not always add to the entire-study totals because of differences in the (small) amounts of missing data for each variable.