Table 1.
Characteristics of the study population of the original dataset and the imputed datasets.
| Baseline population Original data |
Baseline population Imputed data |
||
|---|---|---|---|
| % | N | % (n = 3,963) | |
| Maternal educational level | 3,807 | ||
| Low | 23.5 | 23.8 | |
| Intermediate | 41.6 | 41.7 | |
| High | 35.0 | 34.5 | |
| Sex | 3,963 | ||
| Female | 48.1 | 48.1 | |
| Male | 51.9 | 51.9 | |
| Older sibling(s) | 3,937 | ||
| Yes | 50.7 | 50.6 | |
| No | 49.4 | 49.4 | |
| Maternal smoking during pregnancya | 3,904 | ||
| Yes | 17.8 | 17.9 | |
| No | 82.2 | 82.1 | |
| Breastfeeding duration | 3,896 | ||
| No breastfeeding | 17.9 | 18.0 | |
| 1-16 weeks | 49.6 | 49.7 | |
| >16 weeks | 32.5 | 32.3 | |
| Smoking in the home | 3,935 | ||
| Yesb | 28.7 | 28.7 | |
| No | 71.3 | 71.3 | |
| Day-care centre attendance | 3,796 | ||
| >= 4 hours per week | 24.4 | 24.2 | |
| <4 hours per week | 75.6 | 75.9 | |
| Eczema at age 8 | 16.0 | 3,233 | 16.4 |
| Asthma symptoms at age 8 | 13.0 | 3,308 | 13.8 |
| Poor general health at age 8 | 24.6 | 3,229 | 26.0 |
| Freq. respiratory infections at age 8 | 3.9 | 3,247 | 4.3 |
| Overweight at age 8c | 11.6 | 2,607 | 12.0 |
| Obesity at age 8 | 2.0 | 2,607 | 2.3 |
| Mean/SDd | Mean/SDd | ||
| Maternal age (years) | 30.3/3.9 | 3,920 | 30.3/3.9 |
| Birthweight child (grams) | 3,507/546 | 3,914 | 3,507/546 |
a smoking by the mother during at least the first four weeks of pregnancy
b smoking by anyone in the home more than once a week
c overweight includes obesity
d standard deviation