Table 2:

Modified Poisson regression models demonstrating the prevalence ratio (PR) of seeking urgent asthma care in the last 12 months for a given increase in pollutant concentration. Overall sample and stratified analysis by neighborhood asthma prevalence are displayed. Neighborhood asthma prevalence modified the association between annual average modeled ambient pollutant concentration at the street-level and urgent asthma care.

	Overall Sample (n=190)			LAPN (n=91)			HAPN (n=99)
	PR	95% CI	P	PR	95% CI	P	PR	95% CI	P	P-interaction
NO2	1.13	1.01, 1.26	0.04	1.60	1.20, 2.14	<0.01	1.07	0.95, 1.21	0.24	<0.01
PM2.5	1.50	0.98, 2.30	0.06	3.58	1.26, 10.1	0.02	1.16	0.72, 1.87	0.55	<0.01
EC	1.02	1.00, 1.04	0.05	1.02	0.99, 1.06	0.15	1.01	0.98, 1.04	0.64	-
O3	0.92	0.79, 1.07	0.27	0.56	0.36, 0.87	<0.01	0.96	0.84, 1.13	0.75	0.03
SO2	0.98	0.83, 1.17	0.88	2.59	1.55, 4.34	<0.01	0.94	0.82, 1.12	0.58	<0.01

All models adjusted for sex, black race, Latino ethnicity, white/Asian/other/mixed race, preventive asthma medication use, exercise-induced wheeze, environmental tobacco smoke exposure, maternal asthma, parental income, building type, apartment unit floor height, maternal hardship, truck route density and neighborhood (only in non-stratified models). P-interaction represents the P value for the interaction term (pollutant x neighborhood).

LAPN: lower asthma prevalence neighborhood; HAPN: higher asthma prevalence neighborhood; PR: prevalence ratio; CI: confidence interval; NO₂: nitrogendioxide; PM_2.5: particulate matter <2.5 microns; EC: elemental carbon; O₃: ground level ozone; SO₂: sulfur dioxide