Table 2.
Associations of maternal and partner smoking during pregnancy with offspring smoking initiation (n = 6484)
| Class (percentage membership)a | P-valueb | |||||
|---|---|---|---|---|---|---|
| Non-smokers (84%) | Experimenters (6%) | Late onset (8%) | Early onset (2%) | |||
| OR (95% CI) | OR (95% CI) | OR (95% CI) | OR (95% CI) | |||
| Mother | Unadjusted | 1 | 1.30 (1.05, 1.61) | 2.00 (1.61, 2.47) | 3.91 (2.94, 5.21) | <0.001 |
| Partially adjusted | 1 | 1.33 (1.06, 1.67) | 1.80 (1.43, 2.26) | 2.89 (2.12, 3.94) | <0.001 | |
| Fully adjusted | 1 | 1.23 (0.97, 1.57) | 1.49 (1.17, 1.90) | 2.27 (1.64, 3.15) | <0.001 | |
| Partner | Unadjusted | 1 | 1.28 (1.07, 1.54) | 2.04 (1.68, 2.47) | 3.31 (2.49, 4.40) | <0.001 |
| Partially adjusted | 1 | 1.28 (1.06, 1.55) | 1.86 (1.52, 2.28) | 2.50 (1.85, 3.37) | <0.001 | |
| Fully adjusted | 1 | 1.22 (1.00, 1.49) | 1.68 (1.35, 2.07) | 1.96 (1.43, 2.70) | <0.001 | |
Partially adjusted model adjusted for sex, maternal age, parity, maternal educational attainment, crowding and housing tenure. Fully adjusted model additionally mutually adjusted for mother or partner smoking. aPercentages in each class of smoking initiation are based on the highest probability of class membership for each individual; bP-value for overall association of the exposure with the outcome from Likelihood Ratio Test. CI = confidence interval; OR = odds ratio.