Table 1 Comparison of birth cohort and study group at each stage of follow-up
Variable | Birth cohorta (n = 7223) n% | 5 years (n = 4249) % | 14 years (n = 4155) % | 21 years (n = 2913) % | |
|---|---|---|---|---|---|
Maternal age (yrs) | |||||
15–19 | 1184 | 16.4 | 12.4 | 12.5 | 11.4 |
20–35 | 5726 | 79.3 | 83.2 | 83.2 | 83.8 |
> 35 | 313 | 4.3 | 4.4 | 4.3 | 4.7 |
Level maternal education | |||||
Incomplete high | 1305 | 18.2 | 16.3 | 16.0 | 15.2 |
Complete high | 4609 | 64.3 | 64.4 | 64.6 | 64.3 |
Post high | 1256 | 17.5 | 19.4 | 19.4 | 20.5 |
Family income (antenatal) | |||||
> $10,400 | 4441 | 65.8 | 71.3 | 71.6 | 72.3 |
< $10,400 | 2308 | 34.2 | 28.7 | 28.4 | 27.7 |
Maternal depression | |||||
No | 6262 | 88.4 | 90.7 | 90.8 | 91.7 |
Yes | 823 | 11.6 | 9.3 | 9.2 | 8.3 |
Gender | |||||
Male | 3758 | 52.0 | 52.1 | 52.1 | 47.5 |
Female | 3465 | 48.0 | 47.9 | 47.9 | 52.5 |
Birth weight | |||||
> 2500 g | 6911 | 95.7 | 96.2 | 96.2 | 96.5 |
< 2500 g | 311 | 4.3 | 3.8 | 3.8 | 3.5 |
Gestation | |||||
> 37 wks | 6927 | 95.9 | 96.1 | 96.1 | 96.1 |
< 37 wks | 296 | 4.1 | 3.9 | 3.9 | 3.9 |