Table 1.
Population characteristics.
| Variable | BAMSE (N = 2,591) | GINI South (N = 653) | GINI/LISA North (N = 958) | MAAS (N = 661) | PIAMA (N = 1,058) | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| n/N | Percent | n/N | Percent | n/N | Percent | n/N | Percent | n/N | Percent | |
| Female sex | 1,268/2,591 | 48.9 | 337/653 | 51.6 | 479/958 | 50.0 | 310/661 | 46.9 | 533/1,058 | 50.4 |
| Respiratory infectionsa | 236/2,592 | 9.1 | 227/650 | 34.9 | 373/938 | 39.8 | 0/661 | 0.0 | 253/1,054 | 24.2 |
| Allergic mother | 432/2,563 | 16.9 | 373/653 | 57.1 | 352/955 | 36.9 | 386/645 | 59.8 | 699/1,058 | 66.1 |
| Allergic father | 460/2,563 | 18.0 | 326/647 | 50.4 | 287/950 | 30.2 | 402/641 | 62.7 | 351/1,055 | 33.3 |
| Current asthmab | 263/2,588 | 10.2 | 25/653 | 3.8 | 41/950 | 4.3 | 118/659 | 17.9 | 105/990 | 10.6 |
| Allergic sensitizationb | 851/2,447 | 34.8 | 228/596 | 38.3 | 246/842 | 29.2 | 180/406 | 44.3 | 395/869 | 45.5 |
| Native ethnicity/nationalityc | 2,023/2,576 | 78.5 | 653/653 | 100.0 | 958/958 | 100.0 | 623/655 | 95.1 | 990/1,044 | 95.7 |
| High maternal SESd | 1,083/2,579 | 42.0 | 381/652 | 58.4 | 338/955 | 35.4 | NA | 407/1,055 | 38.6 | |
| High paternal SESd | 1,000/2,532 | 39.9 | 440/647 | 68.0 | 374/949 | 39.4 | 106/608 | 17.4 | 447/1,043 | 42.9 |
| Older siblings | 1,228/2,591 | 47.4 | 258/651 | 39.6 | 511/955 | 53.5 | 324/643 | 50.4 | 509/1,058 | 48.1 |
| Breastfeeding (≥ 12 weeks) | 2,397/2,516 | 95.3 | 445/640 | 69.5 | 526/924 | 56.9 | 307/630 | 48.7 | 556/1,058 | 52.6 |
| Mother smoked during pregnancy | 311/2,590 | 12.0 | 85/646 | 13.2 | 131/944 | 13.9 | 73/659 | 11.1 | 161/1,044 | 15.4 |
| Smoking at child’s home | ||||||||||
| Early life | 524/2,578 | 20.3 | 102/642 | 15.9 | 255/944 | 27.0 | 277/658 | 42.1 | 266/1,058 | 25.1 |
| Currentb | 468/2,549 | 18.4 | 133/653 | 20.4 | 344/953 | 36.1 | 241/649 | 37.1 | 155/990 | 15.7 |
| Use of natural gas for cooking | ||||||||||
| Early life | 285/2,591 | 11.0 | 44/643 | 6.8 | 47/938 | 5.0 | 520/660 | 78.8 | 875/1,053 | 83.1 |
| Currentb | 185/2,584 | 7.2 | 43/653 | 6.8 | 37/948 | 3.9 | 529/661 | 80.0 | 801/1,047 | 76.5 |
| Mold/dampness in child’s home | ||||||||||
| Early life | 653/2,582 | 25.3 | 204/643 | 31.7 | 199/937 | 21.2 | 116/661 | 17.5 | 297/1,042 | 28.5 |
| Currentb | 254/2,579 | 9.9 | 158/652 | 24.2 | 176/936 | 18.8 | 102/661 | 15.4 | 284/985 | 28.8 |
| Furry pets in home | ||||||||||
| Early life | 382/2,591 | 14.7 | 95/634 | 15.0 | 152/922 | 16.5 | 243/661 | 36.8 | 454/1,056 | 43.0 |
| Currentb | 647/2,583 | 25.1 | 157/652 | 24.2 | 253/951 | 26.6 | 289/661 | 43.7 | 484/970 | 49.9 |
| Child-care center attendancee | 2,148/2,539 | 84.6 | 51/619 | 8.2 | 13/880 | 1.5 | 431/621 | 69.4 | 289/1,032 | 28.0 |
| Study arm | ||||||||||
| Observational cohort | NA | 247/653 | 37.8 | 575/958 | 60.0 | 579/661 | 87.6 | 615/1,048 | 58.7 | |
| Intervention group | NA | 406/653 | 62.2 | 383/958 | 40.0 | 82/661 | 12.4 | 433/1,048 | 41.4 | |
| Movedf | 1,644/2,538 | 64.8 | 340/631 | 53.9 | 323/952 | 33.9 | 365/661 | 55.2 | 551/1,058 | 52.4 |
| Birth weight (g) (mean ± SD)g | 3,530 ± 559 | 2,498 | 3,421 ± 446 | 644 | 3,532 ± 495 | 932 | 3,484 ± 501 | 634 | 3,508 ± 548 | 1,056 |
| NA, not applicable/not available. aBAMSE and MAAS: Respiratory infection at time of lung function measurement; GINI and LISA: Lower or upper respiratory infection during past 4 weeks; PIAMA: Cold or respiratory infection during past 3 weeks. bAt the age of lung function testing. cBAMSE: Scandinavian; GINI and LISA: German; MAAS: Caucasian; PIAMA: Dutch. dSES, socioeconomic status; defined by education for BAMSE, GINI and LISA, and PIAMA and by income (> £ 30,000) in MAAS. eDuring second year of life. fAny change of address between birth and lung function measurement. gN = 2,498; the values in the adjacent “Percent” columns are ns. | ||||||||||