Fig. 3
Estimated changes in (a) PEF and (b) FEV1 with increases in air pollutants in relation to a history of asthma or allergy. The estimated changes and 95% confidence intervals for (a) PEF and (b) FEV1 are shown per increase in interquartile range (IQR) of the concentration of air pollutants in relation to a history of asthma or allergy. A: Subjects with a history of asthma. B: Subjects with a history of allergy other than asthma. C: Subjects without a history of asthma or allergy