Characteristics of the original cohort seen in 1993 (5304 children), the 1997 follow up (1273 children), and the study sample (620 children); results are number (%)
| Original cohort | 1997 Follow up | Retrospective and prospective studies | |||||
|---|---|---|---|---|---|---|---|
| *p<0.001. | †Weighted results, due to oversampling of low birthweight children; ‡in 1997 a minimum wage was worth $107.5. | ||||||
| Sex | (n=5290) | (n=1273) | (n=620) | ||||
| Boys | 2603 (49.2) | 669 (52.6) | 291 (46.9) | ||||
| Girls | 2687 (50.8) | 604 (47.4) | 329 (53.1)* | ||||
| Birth weight (g) | (n=5304) | (n=1264) | (n=615) | ||||
| ≥2500 | 4779 (90.1) | 1138 (90.0) | 553 (89.9) | ||||
| <2500 | 525 (9.9) | 126 (10.0)† | 62 (10.1)† | ||||
| Maternal schooling (years) | (n=5301) | (n=1267) | (n=617) | ||||
| None | 137 (2.6) | 30 (2.4) | 14 (2.3) | ||||
| 1–4 | 1359 (25.6) | 322 (25.4) | 145 (23.4) | ||||
| 5–8 | 2448 (46.2) | 592 (46.7) | 303 (48.9) | ||||
| ≥9 | 1357 (26.6) | 323 (25.5) | 155 (25.0) | ||||
| Family income (minimum wages)‡ | (n=5304) | (n=1248) | (n=606) | ||||
| ≤1 | 984 (18.6) | 215 (17.2) | 102 (16.5) | ||||
| 1–3.0 | 2279 (43.0) | 407 (32.6) | 202 (32.6) | ||||
| 3.1–6.0 | 1218 (23.0) | 343 (27.5) | 159 (25.6) | ||||
| 6.1–10 | 437 (8.2) | 138 (11.1) | 76 (12.3) | ||||
| >10 | 386 (7.3) | 145 (11.6) | 67 (11.1) | ||||