Table 1.
Sample characteristics
| Very Preterm (25–33 weeks) | Late Preterm (34–36 weeks) | Full-term (≥37 weeks) | |
|---|---|---|---|
| Infants | |||
| n | 231 | 513 | 10390 |
| W1 Male (%) | 56.9 | 50.9 | 51.3 |
| W1 Gestational age (weeks) | 30.7 (2.5) | 35.3 (0.8) | 39.9 (1.4) |
| W1 Medical risk at birth | 2.7 (1.0) | 1.5 (1.2) | 0.4 (0.8) |
| W1 Weight at birth (grams) | 2230.8 (632.0) | 2791.1 (423.3) | 3539.8 (482.9) |
| W1 Length at birth (cms) | 43.5 (10.4) | 46.8 (7.4) | 51.0 (6.0) |
| W1 Non-singleton (%) | 29.6 | 21.2 | 2.0 |
| W2 Health issues | 0.8 (1.0) | 0.5 (0.8) | 0.4 (0.7) |
| W2 English as first language (%) | 90.7 | 91.4 | 92.6 |
| W2 Irish as first language (%) | 0.0 | 0.7 | 0.4 |
| Mothers | |||
| n | 231 | 512 | 10389 |
| W1 Maternal quality of attachment | 42.3 (3.6) | 42.5 (2.7) | 42.5 (2.8) |
| W1 Maternal emotional distress | 0.2 (0.9) | 0.1 (0.9) | 0.0 (0.8) |
| W2 Irish ethnicity (%) | 81.3 | 84.0 | 84.8 |
| W2 Roman Catholic (%) | 85.7 | 87.3 | 89.8 |
| W2 Age left education | 18.3 (2.7) | 18.7 (2.7) | 19.0 (2.6) |
| Fathers | |||
| n | 197 | 450 | 9351 |
| W1 Paternal quality of attachment | 24.8 (2.7) | 24.1 (1.7) | 24.2 (1.9) |
| W1 Paternal emotional distress | 0.0 (0.9) | 0.1 (0.9) | 0.0 (0.8) |
| W2 Irish ethnicity (%) | 82.9 | 81.2 | 85.5 |
| W2 Roman Catholic (%) | 85.2 | 87.5 | 89.4 |
| W2 Age left education | 18.3 (2.9) | 18.9 (2.9) | 18.8 (2.8) |
| Household | |||
| W1 Equivalised annual income ([)a | 18759.4 | 18957.0 | 21701.68 |
| W2 Equivalised annual income ([)a | 16141.1 | 17832.1 | 18139.7 |
| W2 People in household | 4.3 (1.2) | 4.3 (1.2) | 4.3 (1.1) |
| W2 Two-parent household (%) | 83.5 | 84.4 | 86.6 |
Note. Unless otherwise stated, values represent means, with standard deviations in parentheses. Infant and household information is based on primary caregiver report. W1 = Data was collected at wave 1; W2 = Data was collected at wave 2.
a
Equivalised income is the annual household disposable income, equivalised for the number of adults and children in the household, so that different-sized households can be compared (for additional information, see Quail et al., 2011).