ORs* (95% CIs) for allergist-diagnosed asthma, per IQR increase in to outdoor NO, NO2, black carbon and PM2.5
| Pollutant (IQR) | NO (12.7 μg/m3) | NO2 (7.2 μg/m3) | Black carbon (1.2 AU) | PM2.5 (4.1 μg/m3) |
| Total (n=184) | 1.2 (0.9 to 1.7) | 1.5 (0.9 to 2.5) | 1.1 (0.7, 1.9) | 3.1 (1.3 to 7.4) |
| Control (n=84) | 1.7 (1.0 to 2.8) | 1.9 (0.9 to 4.0) | 1.2 (0.6, 2.3) | 4.1 (1.2 to 13.8) |
| Intervention (n=100) | 0.8 (0.4 to 1.6) | 1.3 (0.6 to 2.9) | 1.1 (0.5, 2.5) | 2.1 (0.6 to 7.1) |
NO, nitric oxide; NO2, nitrogen dioxide; PM2.5, particulate matter of mean aerodynamic diameter ≤ 2.5 μm.
↵* ORs for total group adjusted for intervention group, atopy at 12 months, ethnicity, gender, mother, father or sibling history of asthma, and maternal post-secondary education.
IQR, interquartile range, based on data from all subjects.