Characteristics of the Infant and Preschool Samples

CharacteristicInfant SampleaPreschool Sampleb
    Serious psychological distress
    Poor general health
    Age, mean (SD), y
        Maternal503231.0 (5.5)483734.6 (5.3)
        Paternal455233.7 (6.0)417337.5 (6.0)
    Born in Australia/New Zealand
    2-parent household
            <12 y31.639.4
            12 y completed35.732.4
            <12 y39.644.3
            12 y completed31.626.3
        Father's employment
        Skilled labor/not in labor force397987.7372189.5
        Unemployed/menial labor55612.343710.5
    Sleep problem50304836
    English spoken at home503089.3483987.6
    Age, mean (SD), mo50338.8 (2.6)483956.9 (2.6)
    Birth weight, mean (SD), g49993409 (568.8)b
    Term delivery (>36 wk)502493.4b
    Assisted deliverye502937.9b
    First-born child503341.3b
Breastfeeding duration, mean (SD), wk303514.3 (13.7)b
  • — indicates not measured.

  • a A total of 5033 mothers and 4553 fathers in the infant sample.

  • b A total of 4839 mothers and 4174 fathers in the preschool sample.

  • c n is total number of mothers or fathers responding to each item in the questionnaire.

  • d Data not collected for the preschool sample.

  • e Cesarean section, vacuum extraction, forceps, or other.