Table 3 Mean odds ratios (per 10 μg/m3 increase in NO2) from single‐pollutant model, all available studies.
| Studies, n | Odds ratio (95% confidence interval) | |
|---|---|---|
| Wheeze | 5 | 1.01 (0.93–1.10)H |
| Asthma | 5 | 1.02 (0.94–1.09) |
| Bronchitis | 4 | 0.99 (0.88–1.12) |
| Phlegm | 3 | 1.05 (0.95–1.17) |
| Nocturnal cough | 4 | 1.13 (0.94–1.35)H |
| Morning cough | 3 | 1.15 (1.01–1.30) |
| Sensitivity to inhaled allergens | 5 | 1.13 (1.01–1.26)H |
| Hay fever | 5 | 1.04 (0.98–1.11) |
| Itchy rash | 4 | 1.05 (0.98–1.12) |
| Woken by wheeze | 4 | 1.06 (0.89–1.26)H |
| Allergy to pets | 4 | 1.14 (0.99–1.31) |
“H” indicates heterogeneity between study‐specific results (p<0.10).