Table 1 Maternal and child characteristics
| Ā | nā=ā4,634 | |
|---|---|---|
| Ā | Observed | After multiple imputations |
Maternal characteristics | Ā | Ā |
Age (years)* | 31.1 (4.9) | 31.1 (4.9) |
Highest completed education (%) | Ā | Ā |
āNon-completed, primary or secondary | 47.1 (2,050) | 48.2 (2,234) |
āHigher | 52.9 (2,299) | 51.8 (2,400) |
āMissing | 6.2 (285) | - |
Parity (%) | Ā | Ā |
āNulliparity | 61.6 (2,762) | 61.4 (2,844) |
āMultiparity | 38.4 (1,722) | 38.6 (1,790) |
āMissing | 3.2 (150) | - |
History of asthma or atopy (%) | Ā | Ā |
āNo | 61.9 (2,369) | 59.0 (3,734) |
āYes | 38.1 (1,460) | 41.0 (1,900) |
āMissing | 17.4 (805) | - |
Fetal and Child characteristics | Ā | Ā |
Male sex (%) | 49.9 (2,313) | 49.9 (2,313) |
Gestational age at birth (weeks)$ | 39.9 (37.0-42.1) | 39.9 (37.0-42.1) |
Birth weight (grams)* | 3,439 (556) | 3,439 (556) |
Ethnicity (%) | Ā | Ā |
āEuropean | 70.4 (3,144) | 69.9 (3,240) |
āNon-European | 29.6 (1,320) | 30.1 (1,394) |
āMissing | 3.7 (170) | - |
Breastfed (%) | Ā | Ā |
āNo | 7.7 (339) | 8.0 (371) |
āYes | 92.3 (4,089) | 92.0 (4,263) |
āMissing | 4.4 (206) | - |
Day care attendance (%) | Ā | Ā |
āNo | 48.0 (1,894) | 50.0 (2,316) |
āYes | 52.0 (2,050) | 50.0 (2,318) |
āMissing | 14.9 (690) | - |
Pet keeping (%) | Ā | Ā |
āNo | 65.5 (2,399) | 64.6 (2,993) |
āYes | 34.5 (1,263) | 35.4 (1,641) |
āMissing | 21.0 (972) | - |
Lower respiratory tract infections age 1 year (%) | Ā | Ā |
āNo | 86.4 (3,165) | 85.4 (3,957) |
āYes | 13.6 (498) | 14.6 (677) |
āMissing | 21.0 (971) | - |
Lower respiratory tract infections age 2 years (%) | Ā | Ā |
āNo | 87.9 (3,494) | 87.4 (4,052) |
āYes | 12.1 (484) | 12.6 (582) |
āMissing | 14.2 (659) | - |
Lower respiratory tract infections age 3 years (%) | Ā | Ā |
āNo | 93.3 (3,453) | 92.7 (4,294) |
āYes | 6.7 (247) | 7.3 (340) |
āMissing | 20.2 (934) | - |
Smoking of father (%) | Ā | Ā |
āNo | 57.4 (2,153) | 57.4 (2,658) |
āYes | 42.6 (1,599) | 42.6 (1,976) |
āMissing | 19.0 (882) | - |
Fetal smoke exposure (%) | Ā | Ā |
āNo | 86.9 (3,246) | 86.4 (4003) |
āYes | 13.1 (489) | 13.6 (631) |
āMissing | 19.4 (899) | - |
Infant smoke exposure (%) | Ā | Ā |
āNo | 82.3 (3,391) | 81.4 (3,770) |
āYes | 17.7 (728) | 18.6 (864) |
āMissing | 11.1 (515) | - |
Wheezing age 1 year (%) | Ā | Ā |
āNo | 74.0 (2,922) | 74.1 (3,433) |
āYes | 26.0 (1,028) | 25.9 (1,201) |
āMissing | 14.8 (684) | - |
Wheezing age 2 years (%) | Ā | Ā |
āNo | 82.1 (3,358) | 82.6 (3,827) |
āYes | 17.9 (731) | 17.4 (807) |
āMissing | 11.8 (545) | - |
Wheezing age 3 years (%) | Ā | Ā |
āNo | 89.0 (3,417) | 89.4 (4,143) |
āYes | 11.0 (421) | 10.6 (491) |
āMissing | 17.2 (796) | - |