. Author manuscript; available in PMC: 2015 Apr 9.

Published in final edited form as: J Expo Sci Environ Epidemiol. 2013 Jan 23;23(3):315–321. doi: 10.1038/jes.2012.124

Table 5.

Four-pollutant models of outdoor air pollutants with neonatal health care utilization in 2000, 2003, and 2006 Kids Inpatient Database.

	Increment in LOS, days (n = 1,672,700)	Increment in total charges, 2005$ (n = 1,607,113)	Increment in total costs 2005$ (n = 596,591)
Mean PM_2.5, month of birth (µg/m³)	+0.0001 (−0.02, +0.02)	−$115 (−$237, +$4)	+$77 (−$41, +$195)
Mean NO₂, month of birth (p.p.b.)	−0.05 (−0.08, −0.01)^*	+$462 (+$219, +$704)^**	−$111 (−$295, +$75)
Mean CO, month of birth (p.p.m.)	+0.13 (+0.004, +0.25)^a	+$3677(+$2420, +$4983)^***	+$1166 (+$542, +$1830)^**
Mean O₃, month of birth (p.p.m.)	−0.06 (−0.26, +0.15)	+$4877(+$3422, +$6428)^***	+$964 (+$21, +$2001)^a

All models control for race, primary expected payer, median income quartile for patient zip code, hospital region, admission month, teaching hospital status, and gender. Missing category were added to model due to univariate significant associations but were insignificant at P > 0.2 in all models.

Insignificant after Bonferroni correction (0.05 > P > 0.0167);

P < 0.0167,

^**

P < 0.001,

^***

P < 0.0001.