Cyclist route choice, traffic-related air pollution, and lung function: a scripted exposure study

Table 4 Paired t -test by subject. Average pollutant exposure for each subject’s high-traffic ride vs. low-traffic ride average

	N*	Mean		Standard error of the mean		p-value	95% CI of difference
		Low-traffic	High-traffic	Low-traffic	High-traffic		Lower	Upper
UFPM (#/cm³)	14	13517.13	19945.34	826.28	2022.87	0.01	1656.84	11199.58
PM_2.5 (μg/m³)	8	4.88	4.53	0.40	0.39	0.60	−1.90	1.19
BC (μg/m³)	15	1.73	2.10	0.90	0.15	0.06	−0.02	0.77
CO (ppm)	13	0.77	0.93	0.03	0.04	0.006	0.05	0.26

*N = number of subjects with high & low measurements for pollutant (i.e., number of pairs) (varied due to equipment failures).

ISSN: 1476-069X