TABLE 3

Correlation coefficient between the prevalence of each disease and the concentration of air pollutants in the study area or smoking rate in Japan

Pollutants	BA			RBA			W
Pollutants	Male	Female	Total	Male	Female	Total	Male	Female	Total
NO	0.708**	0.216	0.502*	−0.040	−0.005	0.014	0.650**	0.660**	0.735**
NO₂	0.665**	0.201	0.457*	−0.050	−0.041	−0.054	0.556**	0.490*	0.550**
SPM	0.803**	0.267	0.644**	0.024	0.024	0.134	0.582**	0.518**	0.682**
Smoking rate	0.741**	0.236	0.517**	−0.002	−0.002	0.057	0.656**	0.593**	0.688**

Correlations are calculated according to Spearman's correlation test. BA: bronchial asthma; RBA: remission bronchial asthma; W: wheeze; NO: nitrogen monoxide; NO₂: nitrogen dioxide; SPM: suspended particulate matter. Spearman's rank correlation analysis; *: p<0.05 (two tailed); **: p<0.01 (two tailed).