Table 7.
Fixed Effects for Models with Reduced Covariates
| Level | Model IV | Model IVa | Model IVb | |
|---|---|---|---|---|
| β (grams) (P-Value) | β (grams) (P-Value) | β (grams) (P-Value) | ||
| AIC | 21594.53 | 21519.07 | 21515.5 | |
| Gender | Male v Female | 142.89(22.36; < 0.001) | 155.81(22.04; < 0.001) | 147.05(22.10; < 0.001) |
| Gestational duration | Weeks | 56.23(6.60; < 0.001) | ||
| Birth order | - | < 0.001 | < 0.001 | < 0.001 |
| 1v3+ | -169.84(34.43; < 0.001) | -178.72(33.76; < 0.001) | -182.39(34.10; < 0.001) | |
| 2v3+ | -115.09(31.58; < 0.001) | -102.30(31.17;0.001) | -130.50(31.37; < 0.001) | |
| Year of birth | 0.021 | 0.018 | 0.025 | |
| (1975 v 1983) | -80.33(55.82;0.152) | -83.91(54.71;0.127) | -85.40(55.12;0.123) | |
| (1976 v 1983) | 50.70(56.64;0.372) | 39.70(55.55;0.476) | 60.70(55.88;0.279) | |
| (1977 v 1983) | -67.24(48.62;0.169) | -85.48(47.84;0.076) | -49.98(48.21;0.302) | |
| (1978 v 1983) | -43.56(46.13;0.347) | -65.23(45.43;0.153) | -29.49(45.63;0.519) | |
| (1979 v 1983) | -76.52(42.42;0.073) | -78.76(41.77;0.061) | -67.50(42.02;0.110) | |
| (1980 v 1983) | 43.95(40.58;0.281) | 35.45(40.13;0.378) | 50.35(40.25;0.213) | |
| (1981 v 1983) | 10.01(43.24;0.817) | -0.34(42.71;0.994) | 17.47(42.83;0.684) | |
| (1982 v 1983) | 21.80(42.41;0.608) | 6.61(41.77;0.874) | 24.56(41.94;0.559) | |
| Adequate prenatal care | Yes v No | 108.62(37.24;0.004) | 99.59(36.52;0.006) | 95.28(36.76;0.010) |
| Maternal age | Years | -4.10(3.44;0.233) | -2.86(3.34;0.391) | -4.95(3.37;0.142) |
| Maternal race | White v NonWhite | 211.69(67.95;0.002) | 197.4(65.89;0.003) | 243.75(66.73; < 0.001) |
| Smoking category | < 0.001 | |||
| Avg < 10 cig v None | -150.15(34.85; < 0.001) | |||
| Avg 11-20 cig v None | -248.18(45.08; < 0.001) | |||
| Avg 21+ cig v None | -254.02(71.42;0.001) | |||
| Maternal education | 0.229 | 0.092 | 0.624 | |
| < HS v College | -137.77(82.55;0.097) | -176(80.60;0.031) | -61.88(82.02;0.452) | |
| HS Grad v College | 0.64(28.28;0.982) | -10.35(27.55;0.708) | 11.80(27.81;0.672) | |
| Paternal occupation | 0.116 | 0.033 | 0.243 | |
| Blue v White Collar | -56.66(28.59;0.049) | -66.44(27.87;0.018) | -43.24(28.16;0.127) | |
| Other v White Collar | -2.81(36.96;0.939) | 7.33(36.07;0.839) | 5.01(36.39;0.891) | |
| % Adults living in poverty | > 0% v 0% | -43.96(29.48;0.136) | -39.04(28.66;0.173) | -52.10(28.97;0.072) |
| Mean family income (quartiles) | 0.945 | 0.914 | 0.957 | |
| Q1vQ4 | -11.86(39.32;0.763) | -20.49(38.25;0.593) | -7.88(38.64;0.839) | |
| Q2vQ4 | 0.59(36.71;0.987) | -5.86(35.66;0.870) | 1.29(36.02;0.971) | |
| Q3vQ4 | -19.08(39.04;0.626) | -22.55(37.96;0.553) | -17.43(38.35;0.65) | |
| % Adults graduated | 0.019 | 0.094 | 0.054 | |
| 4 year college (quartiles) | Q1vQ4 | -81.91(38.54;0.035) | -66.80(37.54;0.077) | -67.30(37.92;0.078) |
| Q2vQ4 | -11.96(36.26;0.742) | -15.48(35.28;0.661) | -1.58(35.64;0.965) | |
| Q3vQ4 | 44.29(39.57;0.265) | 30.93(38.49;0.423) | 41.58(38.85;0.286) | |
| % Unemployment | ≤ 10% v > 10% | 26.84(34.02;0.430) | 30.37(33.11;0.359) | 23.33(33.43;0.485) |
‡Type III p-value for overall variation between categories