Early-life exposure to PM2.5 and risk of acute asthma clinical encounters among children in Massachusetts: a case-crossover analysis

Table 2 Odds ratios per IQR increase in PM_2.5 and asthma clinical encounters

	Lag 0^a		Lag 1^b		Lag 2^c
	N	OR (95% CI)	N	OR (95% CI)	N	OR (95% CI)
Crude Model	29,781	1.00 (0.98, 1.02)	29,840	1.00 (0.98, 1.02)	29,828	1.00 (0.98, 1.01)
Adjusted Model^d	28,777	0.99 (0.98, 1.01)	28,829	1.00 (0.98, 1.02)	28,830	0.98 (0.96, 1.00)
Primary/ Secondary Diagnosis only^d	26,185	0.99 (0.97, 1.01)	26,230	1.00 (0.98, 1.02)	26,219	0.98 (0.96, 1.01)

^aLag 0 corresponds to a clinical encounter for the day of exposure
^bLag 1 corresponds to exposure a day prior to clinical encounter
^cLag 2 corresponds to exposure two days prior to clinical encounter
^dAdjusted for lagged temperature, humidity, barometric pressure, and holiday indicator

ISSN: 1476-069X