Table 2.

Descriptive statistics and bivariate chi-square tests between explanatory covariates and race and infant mortality rate (per 1000 live births) among live, singleton births to Black and Non-Hispanic White mothers in Michigan, 1989–2005.

	Overall		Non-Hispanic White		African–American
	(n = 2,087,191)		(n = 9312)		(n = 6514)
	IMR	p	IMR	p	IMR	p
Prenatal care*		<0.001		<0.001		<0.001
Adequate	5.7		4.5		12.4
Inadequate	13.4		10		19.7
Parity		<0.001		<0.001		<0.001
0 previous	6.8		5.4		13.5
1 previous	6.2		4.8		13.3
2+	9		6.3		17.1
Marital status		<0.001		<0.001		<0.001
Unmarried	12.5		8.9		16.7
Married	5.2		4.6		12
Maternal age		<0.001		<0.001		<0.001
<20	11.7		9.5		15.2
20–35	7		5.2		15.2
36+	7.6		5.7		19.3
Education		<0.001		<0.001		<0.001
<12 years	12.5		9.6		17.4
12 years	8.1		6.1		15.3
>12 years	5		3.9		12
Payment source		<0.001		<0.001		<0.001
Private insurance	5.8		4.6		13.8
Medicaid, self-pay, other	11.1		8.2		16.5
Mother US born		<0.001		<0.001		<0.001
Yes	7.6		5.6		15.2
No	4.9		4.4		9.7
Alcohol use		<0.001		<0.001		<0.001
None	7.2		5.4		14.7
Yes	16.6		10.5		33.7
Smoking		<0.001		<0.001		<0.001
None	6.5		4.7		13.7
Yes	11.2		8.7		22.9

^*The Kessner/Institute of Medicine Adequacy of Prenatal Care Index (Kessner et al., 1973) was calculated and analyzed as a binary variable denoting adequate vs. inadequate prenatal care.