Asthma according to birth weight categories
| Boys | Girls | |
| OR (95% CI) | OR (95% CI) | |
| <2500 g (n = 69 boys and 86 girls) | ||
| Unadjusted analysis | 2.14 (1.31 to 3.49) | 1.17 (0.68 to 1.99) |
| Adjusted analysis* | 1.62 (0.79 to 3.32) | 1.25 (0.57 to 2.70) |
| >4500 g (n = 99 boys and 37 girls) | ||
| Unadjusted analysis | 0.74 (0.45 to 1.24) | 2.12 (1.05 to 4.27) |
| Adjusted analysis* | 0.76 (0.41 to 1.43) | 0.79 (0.23 to 2.79) |
| Atopy according to birth weight categories | ||
| >4500 g (n = 87 boys and 31 girls) | ||
| Unadjusted analysis | 1.02 (0.62 to 1.68) | 2.26 (1.05 to 4.87) |
| Adjusted analysis* | 1.13 (0.62 to 2.05) | 2.00 (0.69 to 5.78) |
*Adjusted for maternal/paternal history of asthma/eczema, maternal smoking in pregnancy, any environmantal tobacco smoke at home, maternal age at delivery, child’s ethnicity, maternal parity/birth order, maternal social class, gross household income and current body mass index.