Table 1

Prevalence of primary outcomes for respiratory morbidity and primary exposures in the first year of life

Prevalence, n=2456 % (n)
Primary outcomes
Hospital, doctor, or clinic visits for:
    Upper respiratory tract infection
        0–387.6 (2152)
        ≥412.4 (304)
    Wheezing lower respiratory tract illness
        0–188.2 (2166)
        ≥211.8 (290)
    Non-wheezing lower respiratory infection
        088.0 (2161)
        ≥112.0 (295)
Hospital admission for:
    Upper respiratory tract infection 1.5 (37)
    Wheezing lower respiratory tract illness 3.4 (84)
    Non-wheezing lower respiratory tract illness 1.8 (44)
Primary exposures
Gender (male)50.9 (1250)
Gestational age <37 wk10.6 (260)
Smoking in pregnancy (at 18 and 34 wk)40.3 (990)
Older siblings49.6 (1218)
Maternal education (>16 years schooling)35.0 (860)
Maternal age <20 y (mean age 28.12 y) 9.8 (241)
Duration of feeding regime (cumulative %)
Predominant breast feeding stopped by:
    Never breast fed10.6 (260)
    Two months26.9 (661)
    Four months48.4 (1189)
    Six months61.4 (1508)
    Eight months77.8 (1911)
Partial (any) breast feeding stopped by
    Never breast fed10.6 (260)
    Two months21.2 (521)
    Four months37.7 (926)
    Six months48.0 (1179)
    Eight months58.2 (1429)