Table 1.
Demographic characteristics and environmental tobacco smoke (ETS) exposure of the study participants
| Total | Boys | Girls | ||||
|---|---|---|---|---|---|---|
| (n = 5019) | (n = 2432) | (n = 2587) | ||||
| n | % | n | % | n | % | |
| Age, yr | ||||||
| 12 | 3467 | 69.1 | 1696 | 69.7 | 1771 | 68.5 |
| 13 | 1234 | 24.6 | 577 | 23.7 | 657 | 25.4 |
| 14 | 318 | 6.3 | 159 | 6.5 | 159 | 6.1 |
| Parental education, yr† | ||||||
| ≦ 12 | 3163 | 63.5 | 1509 | 62.7 | 1654 | 64.3 |
| 13~15 | 949 | 19.1 | 460 | 19.1 | 489 | 19.0 |
| ≧ 16 | 867 | 17.4 | 437 | 18.2 | 430 | 16.7 |
| Gestational age† | ||||||
| Full term | 4435 | 90.7 | 2113 | 89.6 | 2322 | 91.6 |
| <4 wk early | 315 | 6.4 | 173 | 7.3 | 142 | 5.6 |
| ≧ 4 wk early | 142 | 2.9 | 71 | 3.0 | 71 | 2.8 |
| Family history of asthma† | ||||||
| Yes | 140 | 3.1 | 68 | 3.1 | 72 | 3.1 |
| Family history of atopy*† | ||||||
| Yes | 1257 | 25.0 | 641 | 25.0 | 643 | 25.0 |
| Family income**† | ||||||
| ≦ 400,000 | 1750 | 37.7 | 792 | 35.4 | 958 | 39.8 |
| 410,000~800,000 | 1833 | 39.5 | 911 | 40.7 | 922 | 38.3 |
| ≧ 810,000 | 1060 | 22.8 | 534 | 23.9 | 526 | 21.9 |
| Active smoking | ||||||
| Yes | 37 | 0.7 | 28 | 1.2 | 9 | 0.3 |
| In utero exposure† | ||||||
| Yes | 197 | 3.9 | 82 | 3.4 | 115 | 4.5 |
| Lifetime ETS† | ||||||
| Yes | 2445 | 49.0 | 1176 | 48.7 | 1269 | 49.4 |
| Currently ETS† | ||||||
| Yes | 2241 | 44.9 | 1078 | 44.6 | 1163 | 45.3 |
| Previous ETS only† | ||||||
| Yes | 204 | 4.1 | 98 | 4.1 | 106 | 4.1 |
| Currently amount of ETS***† | ||||||
| 0 | 2778 | 55.8 | 1354 | 56.2 | 1424 | 55.4 |
| ≦ 10 | 1728 | 34.7 | 838 | 34.8 | 890 | 34.6 |
| > 10 | 472 | 9.5 | 217 | 9.0 | 255 | 9.9 |
| Percent of ETS****† | ||||||
| 0 | 2778 | 55.8 | 1354 | 56.3 | 1424 | 55.4 |
| ≦ 20% | 1406 | 28.3 | 693 | 28.8 | 713 | 27.7 |
| > 20% | 791 | 15.9 | 358 | 14.9 | 433 | 16.8 |
| Dad smoking† | ||||||
| Yes | 1794 | 36.0 | 835 | 34.6 | 959 | 37.2 |
| Mom smoking† | ||||||
| Yes | 171 | 3.4 | 69 | 2.9 | 102 | 4.0 |
| Number of smokers† | ||||||
| 0 | 2723 | 54.8 | 1368 | 56.8 | 1355 | 53.0 |
| 1 | 1476 | 29.7 | 695 | 28.9 | 781 | 30.5 |
| 2 | 513 | 10.3 | 238 | 9.9 | 275 | 10.8 |
| ≧ 3 | 253 | 5.1 | 106 | 4.4 | 147 | 5.7 |
*Atopy is defined as allergic rhinitis or atopic eczema.
**New Taiwan dollars per year ($1 US = $ 33 New Taiwan).
***Average cigarettes per day
****Average percent of ETS in lifetime
† Number of subjects does not add up to total N because of missing data.