Table 5.
The effects of SEM, traffic measures and land use on birth weight, small for gestational age and preterm births 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 |
| Socio-demographic indicators | ||||||
| Mother's education | ||||||
| Low (≤ 12 years) | -8.5 | -12.8, -4.2 | 1.18 | 1.14, 1.22 | 1.11 | 1.06, 1.15 |
| High (13–15 years) | Reference | |||||
| College or postgraduate (≥ 16 years) | 6.0 | 2.0, 10.0 | 1.05 | 1.02, 1.08 | 1.05 | 1.01, 1.09 |
| Mother's race | ||||||
| White | Reference | |||||
| African-American | -113.1 | -119.7, -106.4 | * | 1.06 | 1.00, 1.11 | |
| Asian | -192.2 | -198.6, -185.8 | 0.77 | 0.73, 0.82 | ||
| Hispanic | -77.7 | -83.3, -72.1 | 1.02 | 0.97, 1.07 | ||
| APNCU | ||||||
| Inadequate | -53.2 | -59.0, -47.4 | 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 | -11.0 | -14.4, -7.5 | 0.98 | 0.96, 1.01 | 9.05 | 8.67, 9.45 |
| Median household income† | 6.8 | 4.3, 9.3 | 0.93 | 0.92, 0.95 | 0.99 | 0.98, 1.01 |
| Measures of traffic and land use† | ||||||
| Cumulative traffic density | -0.4 | -2.0, 1.3 | 1.02 | 1.00, 1.03 | 1.00 | 0.98, 1.01 |
| Distance to major highways (meters) | 3.8 | 1.9, 5.7 | 0.99 | 0.97, 1.00 | 1.00 | 0.98, 1.01 |
| % land use for recreation and conservation (open space) | 4.4 | 2.1, 6.6 | 0.98 | 0.97, 1.00 | 0.99 | 0.97, 1.00 |
APNCU – adequacy of prenatal care utilization; CI – confidence interval; OR – odds ratio; SD – standard deviation; SEM – socioeconomic measures
All variables in this table were included in one model. Models 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 distribution of median household income by census tract, 1 SD change of log-transformed traffic exposures, and 1 SD change of in distribution % open space by census tract.