3
| Cold dry air | 23 | Mother smokes v not |
0.815
| 0.38 to 1.72 | Adjusted for sex. Current respiratory illness excluded. Only two children actively smoked |
11
| Exercise + cold air | 40 | Smoking families v not |
2.60
| 1.02 to 6.65 | Asthmatics and active smokers excluded |
12
| Exercise | 12 | Salivary cotinine >3.6 ng/ml v ND |
1.01
| 0.47 to 2.15 | Asthmatics, those with recent symptoms and active smokers excluded |
13
| Exercise | 7 | Mother smokes v not |
1.07
| 0.68 to 1.68 | Unadjusted |
| | | Mother smoked at 1 year | 1.53 | 0.98 to 2.40 | |
| | | Mother smoked while pregnant | 1.16 | 0.65 to 2.05 | |
18
| Exercise | 7 | Mother smokes at home v not |
1.86
| 1.07 to 3.26 | Matched for sex, age and classroom. Active smoking not mentioned |
| | | Father smokes at home v not | 1.05 | 0.63 to 1.76 | |
| | | Mother smokes at home v neither | 2.23 | 1.06 to 4.69 | |
9
2-150
| Carbachol | 45 | Mother smokes v neither |
1.89
| 0.85 to 4.21 | Adjusted for sex |
| | | Father smokes v neither | 2.21 | 1.06 to 4.59 | |
| | | Both smoke v neither | 2.31 | 1.13 to 4.75 | |
| | | Father only smokes | 2.88 | 1.29 to 6.45 | |
10
| Methacholine | 16 | Smoking mothers v not |
0.77
| 0.36 to 1.63 | Asthmatics excluded. Active smoking ignored |
19
2-150
| Methacholine | 51 | Mother smokes v neither |
1.34
| 1.01 to 1.78 | Adjusted for sex. Adjustment for a wide range of confounders reduced odds to 1.30 |
| | | Both smoke v neither | 1.31 | 0.94 to 1.84 | |
| | | Father only v neither | 1.13 | 0.82 to 1.55 | |
20
| Methacholine | 43 | Mother smokes daily v not |
1.23
| 0.76 to 1.99 | Unadjusted. Active smoking not mentioned |
| | | Mother smoked first year v not | 0.815 | 0.5 to 1.33 | |
| | | Mother smoked when pregnant | 0.80 | 0.48 to 1.33 | |
| | | Father smokes daily v not | 0.94 | 0.58 to 1.54 | |
15
| Histamine | 24 | Any smoker in home v none | 1.30 | 0.92 to 1.84 | Adjusted for age, sex, area, house dust mite atopy |