Mean odds ratios (per 10 μg/m3 increase in pollutant) within subset of studies having both pollutant measures
| Studies, n | Odds ratio (95% confidence interval) | ||||
|---|---|---|---|---|---|
| NO2 | Second pollutant | ||||
| Single-pollutant model | Two-pollutant model | Single-pollutant model | Two-pollutant model | ||
| Columns 3 and 4 compare mean estimates of NO2 effects from one- and two-pollutant models, in studies with SO2 data (1st row), or with PM10 data (2nd row). Columns 5 and 6 similarly compare estimates for the corresponding second pollutant. “H” indicates heterogeneity between study-specific results (p<0.10). | |||||
| Wheeze | |||||
| Studies with SO2 data | 4 | 0.99 (0.93–1.05) | 0.99 (0.89–1.10)H | 1.03 (0.96–1.11) | 1.08 (1.02–1.13) |
| Studies with PM10 data | 4 | 1.05 (0.94–1.18) | 1.10 (0.98–1.24) | 1.01 (0.87–1.17) | 0.98 (0.80–1.20) |
| Asthma | |||||
| Studies with SO2 data | 4 | 1.01 (0.93–1.10) | 1.03 (0.92–1.14) | 0.98 (0.88–1.09) | 0.94 (0.82–1.08) |
| Studies with PM10 data | 4 | 1.03 (0.89–1.20) | 1.03 (0.84–1.26) | 1.02 (0.85–1.23) | 1.11 (0.84–1.47) |
| Bronchitis | |||||
| Studies with SO2 data | 3 | 1.02 (0.86–1.22)H | 0.89 (0.76–1.04) | 1.02 (0.92–1.13) | 1.41 (0.87–2.28)H |
| Studies with PM10 data | 3 | 1.05 (0.82–1.33) | 0.99 (0.67–1.46) | 1.35 (0.96–1.91) | 1.49 (0.85–2.61) |
| Phlegm | |||||
| Studies with SO2 data | 2 | 1.02 (0.96–1.07) | 1.01 (0.94–1.08) | 1.01 (0.95–1.08) | 1.01 (0.94–1.09) |
| Studies with PM10 data | 2 | 1.14 (0.95–1.37) | 1.06 (0.75–1.51) | 1.55 (1.11–2.18) | 1.55 (1.01–2.38) |
| Nocturnal cough | |||||
| Studies with SO2 data | 3 | 1.15 (0.89–1.49)H | 1.15 (0.86–1.52)H | 1.19 (0.86–1.66)H | 1.03 (0.79–1.34) |
| Studies with PM10 data | 3 | 1.19 (0.94–1.51)H | 1.21 (0.94–1.56) | 1.14 (0.68–1.91)H | 0.79 (0.53–1.19) |
| Morning cough | |||||
| Studies with SO2 data | 3 | 1.16 (1.02–1.33) | 1.20 (1.03–1.40) | 0.99 (0.89–1.10) | 0.98 (0.88–1.08) |
| Studies with PM10 data | 3 | 1.15 (1.01–1.30) | 1.04 (0.90–1.20) | 1.42 (1.04–1.92) | 1.36 (0.87–2.13) |
| Sensitivity to inhaled allergens | |||||
| Studies with SO2 data | 4 | 1.07 (0.97–1.19)H | 1.10 (0.96–1.27)H | 1.01 (0.94–1.08) | 0.99 (0.90–1.09) |
| Studies with PM10 data | 4 | 1.19 (1.04–1.36) | 1.24 (1.08–1.43) | 1.18 (0.99–1.41) | 0.98 (0.70–1.38) |
| Hay fever | |||||
| Studies with SO2 data | 4 | 1.03 (0.97–1.10) | 1.02 (0.94–1.11) | 1.05 (0.90–1.22) | 1.03 (0.88–1.21) |
| Studies with PM10 data | 4 | 1.04 (0.89–1.22) | 1.03 (0.83–1.28) | 1.22 (0.84–1.76)H | 1.18 (0.70–1.97) |
| Itchy rash | |||||
| Studies with SO2 data | 3 | 1.01 (0.98–1.05) | 0.98 (0.93–1.03) | 1.08 (1.00–1.15) | 1.11 (1.01–1.23) |
| Studies with PM10 data | 3 | 1.11 (1.01–1.22) | 1.20 (0.90–1.60)H | 1.18 (0.94–1.50) | 0.91 (0.48–1.71)H |
| Woken by wheeze | |||||
| Studies with SO2 data | 3 | 0.98 (0.87–1.11) | 0.95 (0.76–1.19)H | 1.05 (0.89–1.24) | 1.14 (0.94–1.38) |
| Studies with PM10 data | 3 | 1.15 (0.92–1.42) | 1.26 (1.01–1.57) | 1.14 (0.77–1.68) | 0.92 (0.56–1.51) |
| Allergy to pets | |||||
| Studies with SO2 data | 3 | 1.06 (0.97–1.15) | 1.05 (0.86–1.30) | 1.19 (1.01–1.40) | 1.08 (0.70–1.66) |
| Studies with PM10 data | 3 | 1.22 (1.02–1.45) | 1.38 (1.00–1.90) | 1.25 (0.92–1.70) | 0.87 (0.42–1.80)H |