| Healthy | Asthmatic | p-value | |
| Children n | 66 | 50 | |
| Age years | 7.8 (7.7–7.9) | 8.4 (7.8–9.4) | <0.0001 |
| Sex female/male n | 26/40 | 17/33 | 0.55 |
| Birth weight g | 3310 (3060–3560) | 3300 (2970–3550) | 0.54 |
| Birth weight z-score | −0.07 (−0.50–0.43) | −0.19 (−0.81–0.50) | 0.58 |
| Maternal tobacco smoke during pregnancy | 9# (15) | 9 (18) | 0.64 |
| Current body mass index z-score | 0.02 (−0.41–0.70) | 0.26 (−0.36–1.39) | 0.14 |
| Current caretakers tobacco smoke | 17¶ (27) | 22+ (45) | 0.06 |
| Caretaker until 2 years of age | <0.0001 | ||
| Family | 13 | 30 | |
| Nanny | 21 | 9 | |
| Nursery | 27 | 8 | |
| Wheezing before 3 years of age | 25 (38) | 35 (70) | 0.001 |
| Family history | |||
| Eczema and/or allergic rhinitis | 39 (59) | NA | |
| Asthma | 23 (35) | NA | |
| Personal history | |||
| Eczema | 18 (27) | 18§ (38) | 0.25 |
| Allergic rhinitis | 2 (3) | 18 (36) | <0.0001 |
| Food allergy | 2 (3) | 12ƒ (26) | 0.0003 |
| Respiratory allergy | NA | 32/47## (68) | |
| Current exhaled nitric oxide ppb | 11 (8.5–14.8) | NA |
Data are presented as median (interquartile range) or n (%) of the total population (N), unless otherwise stated. NA: not available. #: N=61; ¶: N=62; +: N=49; §: N=48; ƒ: N=46; ##: N=47.