Peak flow variability at baseline
| Congested streets | Uncongested streets | |
|---|---|---|
| On getting up | ||
| No. subjects | 202 | 182 |
| Mean no. days | 13.6 | 12.0 |
| Mean CV of PEFR (SD) | 5.25 (3.40) | 6.40 (4.26) |
| 95% CI | 4.78 to 5.72 | 5.78 to 7.02 |
| On coming in | ||
| No. subjects | 189 | 179 |
| Mean no. days | 11.5 | 13.3 |
| Mean CV of PEFR (SD) | 5.37 (3.83) | 5.85 (3.66) |
| 95% CI | 4.83 to 5.92 | 5.31 to 6.39 |