Table 1. Sample characteristics by tobacco use status, weighted.
| Characteristic |
Full sample (nweighted=15,000) |
Dual use
(nweighted=1,029) |
Exclusive cigarette use (nweighted=2,655) |
Exclusive e-cigarette use (nweighted=398) |
Nonuse of both (nweighted=10,918) |
| Note: The presented results were derived from a weighted sample. n (%), frequency with percentage. Abbreviation: IQR=interquartile range. | |||||
| Male, n (%) | 7,483 (49.9) | 874 (84.9) | 2,351 (88.5) | 287 (72.0) | 3,971 (36.4) |
| Age (years), median (IQR) | 17 (16, 18) | 18 (17, 18) | 17 (17, 18) | 17 (16, 18) | 17 (16, 18) |
| Age group (years), n (%) | |||||
| ≤16 | 2,004 (13.4) | 60 (5.8) | 224 (8.4) | 48 (12.1) | 1,672 (15.3) |
| >16–17 | 5,374 (35.8) | 207 (20.1) | 629 (23.7) | 109 (27.4) | 2,765 (25.3) |
| >17–18 | 3,914 (26.1) | 365 (35.4) | 1,163 (43.8) | 136 (34.1) | 3,711 (34.0) |
| >18 | 3,914 (26.1) | 398 (38.6) | 639 (24.1) | 105 (26.5) | 2,771 (25.4) |
| Urban residence, n (%) | 8,924 (59.5) | 697 (67.7) | 1,866 (70.3) | 201 (50.5) | 6,160 (56.4) |
| School type, n (%) | |||||
| General high schools | 9,977 (66.5) | 355 (34.5) | 1,743 (65.6) | 118 (29.6) | 7,762 (71.1) |
| Vocational high schools | 5,022 (33.5) | 674 (65.5) | 912 (34.4) | 280 (70.4) | 3,156 (28.9) |
| Grade, n (%) | |||||
| 10th | 3,069 (20.5) | 130 (12.6) | 382 (14.4) | 81 (20.5) | 2,476 (22.7) |
| 11th | 4,605 (30.7) | 273 (26.6) | 936 (35.3) | 135 (34.0) | 3,260 (29.9) |
| 12th | 7,326 (48.8) | 626 (60.8) | 1,336 (50.3) | 181 (45.5) | 5,182 (47.5) |