Table 3.

Distributions and correlation matrix of the ambient concentrations of five air pollutants for 398,241 participants at baseline (Pearson correlation).

							Pearson correlation coefficients
Air pollutants	Mean (SD)	Min	Max	25th	75th	IQR	${\mathrm{PM}}_{2.5}$	${\mathrm{PM}}_{\text{coarse}}$	${\mathrm{PM}}_{10}$	${\mathrm{NO}}_2$	${\mathrm{NO}}_{\mathrm{x}}$
${\mathrm{PM}}_{2.5}$ ($\mathrm{\mu }\mathrm{g}/\mathrm{m}³$)	9.97 (1.06)	8.17	21.31	9.27	10.54	1.27	1	—	—	—	—
${\mathrm{PM}}_{\text{coarse}}$ ($\mathrm{\mu }\mathrm{g}/\mathrm{m}³$)	6.42 (0.90)	5.57	12.82	5.84	6.63	0.79	0.216	1	—	—	—
${\mathrm{PM}}_{10}$ ($\mathrm{\mu }\mathrm{g}/\mathrm{m}³$)	19.24 (2.02)	5.92	30.08	18.03	20.36	2.33	0.623	0.513	1	—	—
${\mathrm{NO}}_{\mathrm{x}}$ ($\mathrm{\mu }\mathrm{g}/\mathrm{m}³$)	43.68 (15.54)	19.74	265.94	33.90	50.43	16.53	0.849	0.177	0.626	1	—
${\mathrm{NO}}_2$ ($\mathrm{\mu }\mathrm{g}/\mathrm{m}³$)	29.01 (9.17)	8.86	125.13	22.75	33.62	10.87	0.736	0.233	0.779	0.747	1

Note: —, no data; IQR, interquartile range; max, maximum; min, minimum; ${\mathrm{NO}}_2,\text{\hspace{0.17em}nitrogen\hspace{0.17em}dioxide}$; ${\mathrm{NO}}_{\mathrm{x}},\text{\hspace{0.17em}nitrogen\hspace{0.17em}oxides}$; ${\mathrm{PM}}_{2.5},\text{\hspace{0.5em}particulate\hspace{0.17em}matter\hspace{0.17em}with\hspace{0.17em}diameter\hspace{0.17em}of}\le 2.5\mathrm{\hspace{0.17em}\mu }\mathrm{m}$; ${\mathrm{PM}}_{\text{coarse}},\text{\hspace{0.5em}particulate\hspace{0.17em}matter\hspace{0.17em}with\hspace{0.17em}diameters\hspace{0.17em}of\hspace{0.17em}}2.5–10\mathrm{\mu }\mathrm{m}$; ${\mathrm{PM}}_{10},\text{\hspace{0.17em}particulate\hspace{0.17em}matter\hspace{0.17em}with\hspace{0.17em}diameter\hspace{0.17em}of}\le 10\mathrm{\mu }\mathrm{m}$; SD, standard deviation.