Table 2.
Basic characteristics of all studied adolescents
| Group; mean ± SD* | |||
|---|---|---|---|
|
|
|||
| Characteristic | Nonexposed | Exposed | p value† |
| Sex, no. male:female | 258:241 | 208:249 | 0.06 |
| Age, yr | 14.5 ± 1.8 | 14.6 ± 1.8 | 0.61 |
| Family income, $CAD/yr | 51 424 ± 17 446 | 50 518 ± 19 417 | 0.53 |
| Current smoking, yes:no‡ | 36:459 | 54:395 | 0.013 |
| PEMCS, cigarettes/d | 0 | 10.6 ± 6.7 | N/A |
| Gestational duration, wk | 39.3 ± 1.5 | 39.2 ± 1.5 | 0.65 |
| Birth weight, g | 3511 ± 457 | 3265 ± 475 | < 0.001 |
| Breastfeeding duration, wk | 10.5 ± 13.8 | 6.3 ± 11.2 | < 0.001 |
N/A = not applicable; PEMCS = prenatal exposure to maternal cigarette smoking; SD = standard deviation.
*
Unless otherwise indicated.
†
We use a t test for continuous variables and a χ2 test for categorical variables.
‡
Adolescents were classified as currently smoking if they reported to have smoked at least 1 cigarette in the last 30 days. Data were missing from 12 adolescents.