Table 4 Relative risk for multi-pollutants by quartile bins of concentrations during study period
| Â | Q 1 | Q 2 | Q 3 | Q 4 | ||
|---|---|---|---|---|---|---|
NO2 * | NO2 | NO2 | NO2 | |||
≤ 7 ppb | 8-11 ppb | 11-15 ppb | > 15 ppb | |||
Relative Risk and Confidence Interval | ||||||
Q 1 | O 3 * < 28 ppb | Cases | 967 | 982 | 609 | 509 |
Days | 249 | 232 | 141 | 117 | ||
O 3 | 0.93 (0.91-0.94) | 0.91 (0.89-0.92) | 0.93 (0.92-0.94) | 0.93 (0.91-0.95) | ||
NO 2 | 0.55 (0.51-0.59) | 0.84 (0.81-0.86) | 0.96 (0.94-0.99) | 1.20 (1.17-1.23) | ||
Q 2 | O 3 28-36 ppb | Cases | 737 | 820 | 574 | 705 |
Days | 194 | 184 | 122 | 146 | ||
O 3 | 1.00 (0.99-1.02) | 1.00 (0.99-1.01) | 1.01 (1.00-1.02) | 1.00 (0.98-1.02) | ||
NO 2 | 0.45 (0.41-0.50) | 0.83 (0.80-0.86) | 0.96 (0.94-0.99) | 1.24 (1.21-1.27) | ||
Q 3 | O 3 36-48 ppb | Cases | 500 | 972 | 669 | 747 |
Days | 131 | 235 | 150 | 152 | ||
O 3 | 1.06 (1.05-1.07) | 1.04 (1.03-1.05) | 1.02 (1.01-1.03) | 1.02 (1.01-1.03) | ||
NO 2 | 0.56 (0.52-0.61) | 0.81 (0.79-0.83) | 1.03 (1.00-1.06) | 1.27 (1.24-1.30) | ||
Q 4 | O 3 > 48 ppb | Cases | 191 | 746 | 1074 | 952 |
Days | 48 | 189 | 245 | 217 | ||
O 3 | 1.13 (1.10-1.16) | 1.09 (1.08-1.11) | 1.07 (1.06-1.08) | 1.06 (1.04-1.07) | ||
NO 2 | 0.76 (0.67-0.85) | 0.86 (0.83-0.90) | 1.12 (1.09-1.15) | 1.44 (1.38-1.50) | ||