Table 6. Odds ratios for symptoms reported in the diary panel sub-cohort in 2007 and in 2008 relative to 2006, adjusted for change in the control zone, (n = 380).
| Symptoms measured by diary | 2007 vs 2006 | 2008 vs 2006 | |||
| Odds Ratioa | P | Odds Ratioa | P | ||
| (95% CI) | (95% CI) | ||||
| Day symptoms | |||||
| Reduced exp zone | Baseline model | 0.7 (0.2, 1.7) | 0.4 | 0.6 (0.2, 1.6) | 0.3 |
| Adjustedb | 0.6 (0.2, 1.6) | 0.3 | 0.5 (0.2, 1.4) | 0.2 | |
| Increased exp zone | Baseline model | 0.4 (0.1, 1.1) | 0.06 | 0.4 (0.1, 1.3) | 0.1 |
| Adjusted | 0.3 (0.1, 0.9) | 0.04 | 0.4 (0.1, 1.1) | 0.09 | |
| Stack zone | Baseline model | 1.1 (0.4, 2.9) | 0.9 | 0.5 (0.2, 1.4) | 0.2 |
| Adjusted | 1.1 (0.4, 2.8) | 0.9 | 0.4 (0.2, 1.3) | 0.1 | |
| Night symptoms | |||||
| Reduced exp zone | Baseline model | 1.0 (0.4, 2.7) | 1.0 | 0.6 (0.2, 1.6) | 0.3 |
| Adjusted | 1.0 (0.4, 2.8) | 1.0 | 0.5 (0.2, 1.4) | 0.2 | |
| Increased exp zone | Baseline model | 0.4 (0.2, 1.2) | 0.1 | 0.5 (0.2, 1.4) | 0.2 |
| Adjusted | 0.5 (0.2, 1.3) | 0.1 | 0.4 (0.1, 1.2) | 0.1 | |
| Stack zone | Baseline model | 1.4 (0.5, 3.8) | 0.5 | 1.1 (0.4, 3.0) | 0.9 |
| Adjusted | 1.5 (0.5, 4.0) | 0.5 | 1.0 (0.4, 2.8) | 1.0 | |
| Symptom days | |||||
| Reduced exp zone | Baseline model | 1.2 (0.4, 3.6) | 0.7 | 0.6 (0.2, 2.0) | 0.4 |
| Adjusted | 1.1 (0.4, 3.4) | 0.8 | 0.6 (0.2, 1.9) | 0.4 | |
| Increased exp zone | Baseline model | 0.5 (0.1, 1.4) | 0.2 | 0.8 (0.3, 2.6) | 0.7 |
| Adjusted | 0.4 (0.1, 1.2) | 0.1 | 0.6 (0.2, 2.0) | 0.4 | |
| Stack zone | Baseline model | 2.4 (0.8, 7.1) | 0.1 | 1.8 (0.6, 5.6) | 0.3 |
| Adjusted | 2.5 (0.8, 7.5) | 0.1 | 1.6 (0.5, 4.9) | 0.4 | |
| Upper respiratory symptoms | |||||
| Reduced exp zone | Baseline model | 0.6 (0.2, 1.6) | 0.3 | 0.5 (0.2, 1.4) | 0.2 |
| Adjusted | 0.5 (0.2, 1.5) | 0.2 | 0.4 (0.1, 1.2) | 0.1 | |
| Increased exp zone | Baseline model | 0.2 (0.07, 0.6) | 0.005 | 0.1 (0.04, 0.4) | 0.001 |
| Adjusted | 0.2 (0.07, 0.6) | 0.005 | 0.1 (0.04, 0.4) | <0.001 | |
| Stack zone | Baseline model | 0.8 (0.3, 2.3) | 0.7 | 0.3 (0.1, 0.9) | 0.03 |
| Adjusted | 0.8 (0.3, 2.2) | 0.6 | 0.3 (0.1, 0.8) | 0.02 | |
| Wheeze | |||||
| Reduced exp zone | Baseline model | 1.2 (0.3, 4.0) | 0.8 | 0.9 (0.3, 3.5) | 0.9 |
| Adjusted | 1.4 (0.4, 4.7) | 0.6 | 1.1 (0.3, 4.0) | 0.9 | |
| Increased exp zone | Baseline model | 0.5 (0.1, 2.0) | 0.3 | 1.2 (0.3, 4.6) | 0.8 |
| Adjusted | 0.5 (0.2, 1.9) | 0.3 | 1.1 (0.3, 4.2) | 0.9 | |
| Stack zone | Baseline model | 2.2 (0.6, 7.5) | 0.2 | 2.9 (0.8, 10.5) | 0.1 |
| Adjusted | 2.6 (0.8, 8.6) | 0.1 | 3.3 (0.9, 11.6) | 0.06 | |
| Cough | |||||
| Reduced exp zone | Baseline model | 0.9 (0.3, 2.3) | 0.8 | 0.4 (0.1, 1.1) | 0.07 |
| Adjusted | 0.8 (0.3, 2.2) | 0.7 | 0.3 (0.1, 0.9) | 0.03 | |
| Increased exp zone | Baseline model | 0.4 (0.1, 1.1) | 0.08 | 0.3 (0.1, 0.9) | 0.03 |
| Adjusted | 0.4 (0.1, 1.1) | 0.06 | 0.2 (0.1, 0.7) | 0.01 | |
| Stack zone | Baseline model | 1.5 (0.5, 4.1) | 0.4 | 0.6 (0.2, 1.8) | 0.4 |
| Adjusted | 1.5 (0.5, 4.1) | 0.4 | 0.5 (0.2, 1.5) | 0.2 | |
a
OR-odds of higher values on the ordinal scale (symptoms experienced: 0 days; 1–10% of days;10–20% of days; and 21–100% of days) compared with lower values, assuming proportional odds.
b
Adjusted for: age; gender; diagnosis of asthma at baseline; smoker; ETS; gas stove or oven; unflued gas heating; education and employment status.