Table IV.
IQ, years of schooling, and income at 30 years of age, according to socioeconomic, demographic, and maternal smoking variables in the pregnancy
| IQ (points), mean (95% CI) | Years of schooling, mean (95% CI) | Monthly income (R$), mean (95% CI) | |
|---|---|---|---|
| Family income at birth (minimum wage) | P < .001 | P < .001 | P < .001 |
| ≤1 | 91.5(90.7-92.4) | 8.9(8.6-9.1) | 940(855-1024) |
| 1.1-3 | 96.6(96.0-97.1) | 10.7(10.6-10.9) | 1255(1191-1320) |
| 3.1-6 | 102.0(101.2-102.9) | 13.1(12.8-13.4) | 1894(1750-2038) |
| 6.1-10 | 106.7(105.2-108.2) | 14.5(14.1-14.9) | 2583(2260-2907) |
| ≥10 | 110.4(108.9-112.0) | 15.8(15.3-16.2) | 3208(2787-3628) |
| Maternal years of schooling at birth | P < .001 | P < .001 | P < .001 |
| 0-4 | 92.2(91.5-92.9) | 9.2(9.0-9.4) | 997(931-1062) |
| 5-8 | 97.5(97.0-98.1) | 11.1(10.9-11.3) | 1356(1281-1430) |
| 9-11 | 103.2(102.1-104.3) | 13.2(12.9-13.5) | 1870(1679-2063) |
| ≥12 | 108.6(107.7-109.5) | 15.3(15.1-15.6) | 2846(2614-3078) |
| Maternal skin color | P < .001 | P < .001 | P < .001 |
| White | 99.2(98.8-99.7) | 11.6(11.5-11.8) | 1616(1548-1683) |
| Non-white | 92.1(91.2-93.0) | 9.9(9.6-10.2) | 977(906-1048) |
| Household assets index(quintiles) | P < .001 | P < .001 | P < .001 |
| First | 90.0(89.1-91.0) | 8.4(8.1-8.7) | 868(797-938) |
| Second | 95.2(94.3-96.0) | 10.3(10.0-10.6) | 1219(1117-1320) |
| Third | 100.4(99.7-101.0) | 12.1(11.9-12.4) | 1564(1466-1662) |
| Fourth | 101.3(100.0-102.6) | 12.7(12.3-13.1) | 1762(1556-1967) |
| Fifth | 104.2(103.1-105.2) | 13.7(13.3-14.0) | 2321(2100-2542) |
| Maternal smoking during pregnancy | P < .001 | P < .001 | P = .001 |
| No | 99.1(98.6-99.6) | 11.7(11.5-11.8) | 1573(1499-1648) |
| Yes | 95.9(95.2-96.6) | 10.7(10.5-10.9) | 1371(1282-1460) |