Table 4. Odds ratios for symptoms reported by questionnaire in 2007 and in 2008 relative to 2006 adjusted for change in the control zone.
| Outcomes measured by questionnaire | 2007 vs 2006 | 2008 vs 2006 | |||
| Odds Ratio (95% CI) | P | Odds Ratio (95% CI) | P | ||
| Upper respiratory symptoms | |||||
| Reduced exp zone | Baseline model | 0.7 (0.5, 1.2) | 0.2 | 0.8 (0.5, 1.3) | 0.3 |
| Adjusted | 0.7 (0.4, 1.2)a | 0.2 | 0.8 (0.5, 1.3)a | 0.3 | |
| Increased exp zone | Baseline model | 2.0 (1.2, 3.6) | 0.02 | 3.2 (1.7, 6.1) | <0.001 |
| Adjusted | 1.9 (1.0, 3.3)a | 0.04 | 3.0 (1.6, 5.6)a | <0.001 | |
| Stack zone | Baseline model | 1.8 (1.1, 3.2) | 0.03 | 1.8 (1.0, 3.2) | 0.05 |
| Adjusted | 1.8 (1.1, 3.1)a | 0.03 | 1.7 (1.0, 3.0)a | 0.07 | |
| Lower respiratory symptoms | |||||
| Reduced exp zone | Baseline model | 0.9 (0.6, 1.3) | 0.7 | 0.9 (0.6, 1.4) | 0.7 |
| Adjusted | 0.9 (0.6, 1.3)b | 0.6 | 0.9 (0.6, 1.4)c | 0.6 | |
| Increased exp zone | Baseline model | 1.5 (1.0, 2.2) | 0.07 | 1.4 (0.8, 2.2) | 0.2 |
| Adjusted | 1.5 (1.0, 2.2)b | 0.08 | 1.4 (0.8, 2.2)c | 0.2 | |
| Stack zone | Baseline model | 1.2 (0.8, 1.7) | 0.5 | 1.6 (1.0, 2.4) | 0.05 |
| Adjusted | 1.2 (0.8, 1.7)b | 0.4 | 1.6 (1.0, 2.5)c | 0.04 | |
| Severe lower respiratory symptoms | |||||
| Reduced exp zone | Baseline model | 1.1 (0.6, 2.0) | 0.9 | 1.0 (0.5, 1.9) | 1.0 |
| Adjusted | 1.1 (0.6, 2.0)d | 0.9 | 1.0 (0.5, 2.0)d | 0.9 | |
| Increased exp zone | Baseline model | 1.2 (0.6, 2.4) | 0.7 | 1.0 (0.5, 2.1) | 1.0 |
| Adjusted | 1.1 (0.5, 2.2)d | 0.8 | 1.0 (0.5, 2.0)d | 0.9 | |
| Stack zone | Baseline model | 3.0 (1.5, 6.0) | 0.002 | 1.4 (0.7, 2.8) | 0.4 |
| Adjusted | 3.2 (1.6, 6.5)d | 0.001 | 1.6 (0.8, 3.3)d | 0.2 | |
| Wheeze in last 3 months | |||||
| Reduced exp zone | Baseline model | 0.9 (0.5, 1.5) | 0.7 | 0.9 (0.5, 1.5) | 0.7 |
| Adjusted | 0.9 (0.5, 1.6)e | 0.8 | 0.7 (0.3, 1.2)f | 0.2 | |
| Increased exp zone | Baseline model | 1.1 (0.6, 2.0) | 0.8 | 1.1 (0.6, 2.0) | 0.8 |
| Adjusted | 1.2 (0.6, 2.2)e | 0.6 | 1.1 (0.5, 2.4)f | 0.7 | |
| Stack zone | Baseline model | 1.8 (1.0, 3.3) | 0.06 | 1.8 (1.0, 3.3) | 0.06 |
| Adjusted | 2.0 (1.1, 3.6)e | 0.03 | 1.5 (0.7, 3.0)f | 0.3 | |
| Cough in last 3 months | |||||
| Reduced exp zone | Baseline model | 0.8 (0.6, 1.1) | 0.2 | 0.9 (0.6, 1.3) | 0.4 |
| Adjusted | 0.8 (0.6, 1.1)g | 0.2 | 0.9 (0.6, 1.3)h | 0.5 | |
| Increased exp zone | Baseline model | 1.4 (0.9, 2.0) | 0.1 | 1.1 (0.7, 1.8) | 0.6 |
| Adjusted | 1.5 (1.0, 2.2)g | 0.06 | 1.2 (0.8, 1.9)h | 0.4 | |
| Stack zone | Baseline model | 1.1 (0.8, 1.7) | 0.5 | 1.2 (0.8, 1.9) | 0.3 |
| Adjusted | 1.1 (0.8, 1.7)g | 0.5 | 1.3 (0.8, 1.9)h | 0.3 | |
a
Adjusted for: asthma, gas cooker or oven.
b
Adjusted for: age, age2, gender, asthma, smoker, unflued gas heater.
c
Adjusted for: age, age2, asthma, smoker, unflued gas heater.
d
Adjusted for: age, age2, asthma, smoker, ETS at home.
e
Adjusted for: asthma, unflued gas heater.
f
Adjusted for: age, age2, asthma, unflued gas heater.
g
Adjusted for: age, age2, asthma, smoker, gas cooker or oven.
h
Adjusted for: age, age2, gender, asthma, smoker, gas cooker or oven.