Table 1.
Descriptive statistics of participant characteristics (entire cohort of live births), by country
| Belgium | Denmark | Estonia | France | Germany | Italy | Netherlands | Poland | Portugal | UK | Sweden | |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Infants (N) | 752 | 351 | 153 | 1307 | 758 | 1134 | 393 | 316 | 724 | 1745 | 267 |
| Gestational age, completed weeks, Mean (SD) | 28.6 (2.3) | 28.0 (2.4) | 28.7 (2.2) | 28.4 (2.3) | 28.2 (2.6) | 28.5 (2.4) | 28.4 (2.5) | 28.1 (2.8) | 28.5 (2.2) | 28.5 (2.4) | 28.2 (2.5) |
| Male, N (%) | 426 (56.6) | 185 (52.7) | 80 (52.3) | 701 (53.6) | 407 (53.7) | 563 (49.6) | 195 (49.6) | 176 (55.7) | 423 (58.4) | 965 (55.3) | 145 (54.3) |
| Singleton, N (%) | 464 (61.7) | 208 (59.3) | 119 (77.8) | 881 (67.4) | 487 (64.2) | 768 (67.7) | 274 (69.7) | 251 (79.4) | 500 (69.1) | 1300 (74.6) | 185 (69.3) |
| Twins or more, N (%) | 288 (38.3) | 143 (40.7) | 34 (22.2) | 426 (32.6) | 271 (35.8) | 366 (32.3) | 119 (30.3) | 65 (20.6) | 224 (30.9) | 443 (25.4) | 82 (30.7) |
| Birth weight (grams), Mean (SD) | 1260.0 (420.8) | 1141.6 (415.4) | 1287.0 (390.1) | 1162.3 (372.1) | 1165.1 (418.0) | 1195.4 (420.3) | 1198.2 (412.1) | 1224.7 (474.2) | 1149.4 (363.5) | 1210.4 (383.9) | 1216.7 (436.4) |
| Follow up at five years of age, N (%) | 280 (37.2) | 152 (43.3) | 134 (87.6) | 779 (59.6) | 280 (36.9) | 693 (61.1) | 155 (39.4) | 189 (59.8) | 433 (59.8) | 448 (25.7) | 144 (53.9) |
UK denotes United Kingdom; SD denotes standard deviation