|  | All asthma | Aged 0-1 at asthma admission | Aged 2+ at asthma admission | |||
---|---|---|---|---|---|---|---|
Characteristics | Â | OR | 95% C.I. | OR | 95% C.I. | OR | 95% C.I |
Maternal asthma | No | 1.00 | - | 1.00 | - | 1.00 | - |
 | Yes | 3.11 | 2.67-3.63 | 3.89 | 2.71-5.57 | 3.07 | 2.61-3.60 |
Social class | 1-2 | 0.81 | 0.74-0.89 | 0.76 | 0.58-0.98 | 0.81 | 0.74-0.89 |
 | 3 | 1.00 | - | 1.00 | - | 1.00 | - |
 | 4-5 | 1.07 | 0.96-1.20 | 1.09 | 0.82-1.47 | 1.04 | 0.94-1.16 |
Sex | Female | 1.00 | - | 1.00 | - | 1.00 | - |
 | Male | 1.82 | 1.66-1.99 | 2.08 | 1.64-2.65 | 1.53 | 1.41-1.66 |
Birth weight (g) | 1000-2999 | 1.20 | 1.09-1.33 | 1.42 | 1.08-1.86 | 1.21 | 1.10-1.33 |
 | 3000-3999 | 1.00 |  | 1.00 |  | 1.00 | - |
 | 4000-5499 | 1.01 | 0.87-1.17 | 0.88 | 0.58-1.34 | 1.06 | 0.92-1.22 |
Gestation age (wks) | 24-37 | - | - | 1.59 | 1.15-2.20 | - | - |
 | 38-41 | - | - | 1.00 | - | - | - |
 | 42-47 | - | - | 1.28 | 0.89-1.83 | - | - |
Smoking | No | 1.00 | - | 1.00 | - | - | - |
 | Yes | 1.13 | 1.02-1.25 | 1.35 | 1.04-1.74 | - | - |
Parity | 0 | - | - | 1.00 | - | - | - |
 | 1 |  |  | 1.34 | 1.03-1.74 |  |  |
 | 2 |  |  | 1.38 | 0.99-1.93 |  |  |
 | 3 |  |  | 2.19 | 1.42-3.38 |  |  |
 | 4+ | - | - | 2.01 | 1.07-3.76 | - | - |
Caesarean | No | 1.00 | - | - | - | - | - |
 | Yes | 1.18 | 1.02-1.34 | - | - | - | - |