Table 1. Characteristics and rates of infants receiving a diagnosis of neonatal abstinence syndrome vs. all other US hospital births, 2018.

LOS: length of stay; NAS: neonatal abstinence syndrome; CI: confidence interval

	NAS rate per 1000 births	NAS n = %, (95% CI)	All other newborn hospitalizations   n = %, (95% CI)	P-value
Overall	7.1 (6.8-7.3)
Sex				0.02
Male	7.4 (7.1-7.6)	52.9 (51.7-54.2)	51.0 (50.9-51.1)
Female	6.8 (6.6-7.0)	47.0 (45.7-48.3)	49.0 (48.8-49.1)
Race/ Ethnicity				< .0001>
White	10.7 (10.3-11.0)	69.8 (67.7-71.9)	46.2 (44.9-47.4)
Black	4.1 (3.7-4.4)	7.7 (6.7-8.7)	13.4 (12.7-14.1)
Hispanic	2.8 (2.5-3.0)	7.2 (6.1-8.2)	18.5 (17.4-19.5)
Native American/ Alaska native	0.5 (0.3-0.8)	0.4 (0.2-0.6)	5.4 (4.9-5.9)
Other	5.2 (4.5-5.8)	5.4 (4.3-6.5)	7.4 (6.8-7.9)
Household income, quartile				< .0001>
1st	9.5 (9.0-9.5)	35.9 (33.6-38.2)	26.8 (25.7-27.9)
2nd	8.2 (7.9-8.6)	30.0 (28.3-31.7)	25.7 (24.9-26.5)
3rd	6.2 (5.9-6.5)	21.5 (20.0-23.1)	24.5 (23.8-25.2)
4th	3.7 (3.5-3.8)	11.4 (10.2-12.6)	22.1 (20.8-23.4)
Payment				< .0001>
Medicaid	13.2 (12.8-13.6)	84.1 (82.8-85.3)	44.7 (43.6-45.9)
Private	1.5 (1.4-1.6)	10.0 (9.0-11.0)	47.1 (45.9-48.3)
Uninsured	6.2 (5.6-6.6)	4.4 (3.7-5.1)	5.1 (4.7-5.5)
Other	3.3 (2.7-3.8)	1.3 (1.0-1.7)	2.9 (2.7-3.1)
Hospital bed-size				0.05
Small	6.8 (6.5-7.1)	18.7 (16.7-20.6)	19.5 (18.3-20.7)
Medium	6.4 (6.0-6.7)	27.6 (25.1-30.2)	30.6 (29.2-31.9)
Large	7.6 (7.3-7.9)	53.7 (50.8-56.6)	49.9 (48.4-51.5)
Urban/ Rural				< .0001>
Rural	10.5 (9.1-11.7)	13.2 (11.1-15.2)	9.0 (8.5-9.4)
Urban non-Teaching	6.2 (5.8-6.5)	16.8 (14.9-18.6)	19.4 (18.4-20.5)
Urban teaching	7.0 (6.7-7.2)	70.1 (67.5-72.6)	71.6 (70.4-72.7)
Delivery hospital region				< .0001>
Northeast	9.4 (8.9-9.9)	21.0 (18.6-23.5)	15.7 (14.6-16.9)
Midwest	6.6 (6.1-7.0)	19.7 (17.5-21.9)	21.3 (20.1-22.4)
South	7.6 (7.2-7.9)	42.2 (39.3-45.2)	39.5 (37.9-41.0)
West	5.1 (4.8-5.4)	17.1 (15.2-18.9)	23.5 (22.3-24.8)