The effects of socioeconomic status and indices of physical environment on reduced birth weight and preterm births in Eastern Massachusetts

Table 3 Independent effects of individual and area-based socioeconomic measures (not including traffic and land use variables) in the study of singleton births in Eastern Massachusetts between 1996 and 2002.

	Birth weight		Small for gestational age		Preterm birth
Model covariates	Change (in grams)	95% CI	OR	95% CI	OR	95% CI
Mother's education
High school or less (≤ 12 years)	-8.6	-12.9, -4.3	1.18	1.14, 1.22	1.11	1.06, 1.15
Some college (13–15 years)	Reference
College or postgraduate (≥ 16 years)	6.0	2.1, 10.0	1.05	1.01, 1.08	1.05	1.01, 1.09
Mother's race
White	Reference
African-American	-112.9	-119.6, -106.3	*		1.06	1.00, 1.11
Asian	-193.0	-199.4, -186.7			0.77	0.73, 0.82
Hispanic	-78.0	-83.6, -72.3			1.02	0.97, 1.07
APNCU
Inadequate	-53.4	-59.2, -47.6	1.26	1.21, 1.31	4.52	4.25, 4.81
Intermediate	-39.0	-44.6, -33.3	1.12	1.08, 1.17	1.91	1.76, 2.08
Appropriate	Reference
Appropriate plus	-11.1	-14.5, -7.6	0.98	0.96, 1.01	9.05	8.67, 9.45
Median household income^†	8.8	6.5, 11.2	0.92	0.91, 0.94	0.99	0.98, 1.01

APNCU – adequacy of prenatal care utilization; CI – confidence interval; OR – odds ratio; SD – standard deviation
Model controlled additionally for mother age, gestational age (for models with birth weight as the outcome), cigarette smoking during pregnancy, previous infant greater than 4000 grams, previous preterm birth, chronic or gestational conditions of mother, and year of birth.
*Race is already controlled for in the definition of "small for gestational age"
^†The effect is for 1 SD change in the median household income by tract

ISSN: 1476-069X