| Personal information | Gender | Total | |
| Males (n = 6) | Females (n = 17) | 23 (100%) | |
| Age (years) |
|
|
|
| · Less than 20 | 0 | 3 (17.65) | 3 (13.04) |
| · 20 - 29 | 3 (50) | 2 (11.76) | 5 (21.74) |
| · 30 - 39 | 2 (33.33) | 3 (17.65) | 5 (21.74) |
| · 40 - 49 | 0 | 6 (35.29) | 6 (26.09) |
| · ≥50 | 1 (16.67) | 3 (17.65) | 4 (17.39) |
| Education level |
|
|
|
| · Primary school | 3 (50) | 8 (47.07) | 11 (47.83) |
| · High school | 2 (33.33) | 6 (35.29) | 8 (34.78) |
| · Vocational | 0 | 1 (5.88) | 1 (4.35) |
| · Bachelor degree | 1 (16.67) | 2 (11.76) | 3 (13.04) |
| Smoking behaviour |
|
|
|
| · Yes—current | 2 (33.33) | 0 | 2 (8.70) |
| · Yes—past | 1 (16.67) | 0 | 1 (4.35) |
| · Never | 3 (50) | 17 (100) | 20 (86.95) |