Multivariable associations of birth weight with FEV1
| Difference (95% confidence interval) in FEV1 (l) | ||||
|---|---|---|---|---|
| Model 1* | Model 2† | Model 3‡ | Model 4§ | |
| FEV1, forced expiratory volume in 1 second. | ||||
| *Model 1: adjusted for age and examining nurse. | ||||
| †Model 2: adjusted for age, examining nurse and height squared. | ||||
| ‡Model 3: adjusted for age, examining nurse, height squared, father’s occupational social class, whether childhood house had a bathroom, whether childhood house had hot water, family access to a car in childhood, whether the participant shared a bedroom as a child, age at leaving full time education, adult occupational social class, adult car access, adult home ownership, pension arrangements. | ||||
| §Model 4: adjusted for all factors in model 3 and adult smoking. | ||||
| Lowest quarter birth weight,range 739–2826 g (N = 746) | Reference | Reference | Reference | Reference |
| 2nd quarter birth weight,range 2827–3352 g (N = 476) | 0.07 (0.00 to 0.13) | 0.01 (−0.05 to 0.07) | −0.01 (−0.07 to 0.05) | −0.01 (−0.07 to 0.05) |
| 3re quarter birth weight,range 3353–3735 g (N = 774) | 0.11 (0.05 to 0.15) | 0.02 (−0.03 to 0.08) | 0.02 (−0.03 to 0.07) | 0.02 (−0.03 to 0.07) |
| Highest quarter birth weight,range 3736–5909 g (N = 435) | 0.13 (0.06 to 0.19) | 0.01 (−0.06 to 0.07) | 0.00 (−0.06 to 0.06) | 0.00 (−0.07 to 0.06) |
| Per 1 kg birth weight | 0.07 (0.04 to 0.10) | 0.01 (−0.02 to 0.04) | 0.01 (−0.02 to 0.04) | 0.01 (−0.02 to 0.04) |
| p linear trend | < 0.001 | 0.48 | 0.47 | 0.42 |
| p non-linear association | 0.43 | 0.27 | 0.55 | 0.69 |
| Per 1 kg excluding those in lowest birth weight quarter | 0.04 (−0.02 to 0.09) | 0.00 (−0.05 to 0.05) | 0.00 (−0.05 to 0.05) | 0.01 (−0.04 to 0.06) |