Table 1.
Demographic and Neonatal characteristics: participants versus non-participants
| Total | Participants | Non-participants | Participants vs non-participants | ||||
|---|---|---|---|---|---|---|---|
| % | N | % | N | % | N | p-value | |
| Gender | 0.000 | ||||||
| Female | 48.2 | 461 | 62.7 | 188 | 41.6 | 273,384 | |
| Male | 51.8 | 496 | 37.3 | 112 | 58.4 | ||
| Origin | 0.000 | ||||||
| Caucasian | 85.3 | 810 | 93.6 | 278 | 81.5 | 532 | |
| Non-Caucasian | 14.7 | 140 | 6.4 | 19 | 18.5 | 121 | |
| Highest educational level parents a,b | |||||||
| Low | 38.9 | 340 | 26.8 | 78 | 44.9 | 262 | 0.000 |
| Middle | 36.3 | 317 | 39.2 | 114 | 34.8 | 203 | |
| High | 24.8 | 217 | 34.0 | 99 | 20.2 | 118 | |
| Social economic level parent c | 0.000 | ||||||
| Very low | 10.1 | 95 | 3.4 | 10 | 13.3 | 85 | |
| Low | 32.3 | 302 | 27.2 | 81 | 34.6 | 221 | |
| Bit low | 22.0 | 206 | 22.1 | 66 | 21.9 | 140 | |
| Bit high | 9.0 | 84 | 10.4 | 31 | 8.3 | 53 | |
| High | 16.2 | 152 | 21.5 | 64 | 13.8 | 88 | |
| Very high | 10.4 | 97 | 15.4 | 46 | 8.0 | 51 | |
| Maternal age at time of birth (yrs) d | |||||||
| Mean (SD) | 27.2 (4.9) | 28.2 (4.3) | 26.8 (5.0) | 0.000 | |||
| range | 13.3–43.6 | 18.0–42.6 | 13.3–43.6 | ||||
| < 20 | 5.2 | 49 | 0.7 | 2 | 7.2 | 47 | 0.000 |
| ≥ 20 and < 36 | 90.9 | 855 | 94.5 | 275 | 89.2 | 580 | |
| ≥36 | 3.9 | 37 | 4.8 | 14 | 3.5 | 23 | |
| Birth weight (grams) | |||||||
| Mean (SD) | 1313.3 (282.7) | 1312.5 (305.9) | 1313.7 (271.7) | 0.951 | |||
| range | 560–2580 | 560–2580 | 600–2400 | ||||
| ≤ 1000 | 14.5 | 139 | 14.7 | 44 | 14.5 | 95 | 0.353 |
| 1001–1250 | 27.0 | 258 | 28.3 | 85 | 26.3 | 173 | |
| 1251–1500 | 38.6 | 369 | 34.7 | 104 | 40.3 | 265 | |
| > 1500 | 20.0 | 191 | 22.3 | 67 | 18.9 | 124 | |
| Gestational age (weeks) e | |||||||
| Mean (SD) | 31.0 (2.5) | 31.0 (2.3) | 31.1 (2.6) | 0.534 | |||
| range | 25.4–40.9 | 26.0–37.6 | 25.4–40.9 | ||||
| Appropriate for gestational age (yes) e | 62.8 | 600 | 61.2 | 183 | 63.6 | 417 | 0.516 |
| Mechanical ventilation (days) f | |||||||
| Mean (SD) | 4.8 (9.5) | 4.7 (8.0) | 4.8 (10.1) | 0.823 | |||
| range | 0.0–117.0 | 0.0–43.0 | 0.0–117.0 | ||||
| None | 0.0 | 0 | 0.0 | 0 | 0.0 | 0 | 0.741 |
| 1–7 | 79.1 | 756 | 78.3 | 235 | 79.4 | 521 | |
| 8–28 | 17.5 | 167 | 18.7 | 56 | 16.9 | 111 | |
| > 28 | 3.5 | 33 | 3.0 | 9 | 3.7 | 24 | |
| IRDS (yes) | 39.0 | 373 | 42.3 | 127 | 37.4 | 246 | 0.154 |
| ICH (yes) | 17.2 | 165 | 19.0 | 57 | 16.4 | 108 | 0.356 |
| Disability at age 14 g | 0.029 | ||||||
| none | 49.8 | 421 | 51.9 | 149 | 48.7 | 272 | |
| impairment (1 or 2 small) | 27.7 | 234 | 30.3 | 87 | 26.3 | 147 | |
| mild disability (> 2 small or 1 large) | 16.3 | 138 | 14.6 | 42 | 17.2 | 96 | |
| severe disability (> 1 large) | 6.3 | 53 | 3.1 | 9 | 7.9 | 44 | |
Participants: Survivors of the POPS cohort at age 28 who completed the Course of Life Questionnaire
Non-participants: Survivors of the POPS cohort at age 28 who did not complete the Course of Life Questionnaire
aLow = primary education, lower vocational education; Middle = general secondary education, middle vocational education; High = higher vocational education, university
IRDS: idiopathic respiratory distress syndrome; ICH: intracerebral hemorrhage
b83 unknown: participants 9, non-participants 74
c21 unknown: participants 2, non-participants 19
d16 unknown: participants 9, non-participants 7
e2 unknown: participants 2, non-participants 0
f1 unknown: participants 0, non-participants 1
g111 unknown: participants 13, non-participants 98