| Demographic variable | N (%) | |
| Age | 18 - 19 years old | 153 (21.5%) |
| 20 - 22 years old | 458 (64.6%) | |
| 23 - 25 years old | 98 (13.9%) | |
| Sex | Male | 333 (47.0%) |
| Female | 376 (53.0%) | |
| Year of study | 1st and 2nd year | 261 (36.8%) |
| 3rd and 4th year | 330 (46.5%) | |
| 5th year and above | 118 (16.6%) | |
| Faculty | Dental students | 310 (43.7%) |
| Engineering, computer science, science and literature, others (religion, economy and education) | 226 (31.9%) | |
| Medicine, nursing and pharmacy | 173 (24.4%) | |
| Educational level/father | Less than university education | 257 (36.2%) |
| University or higher education | 452 (63.8%) | |
| Educational level/mother | Less than university education | 459 (64.7%) |
| University or higher education | 250 (35.3%) | |
| Number of family members | <5 members | 54 (7.6%) |
| 5 - 6 members | 246 (34.7%) | |
| >6 members | 409 (57.7%) | |
| Smoking | Yes | 356 (50.2%) |
| No | 353 (49.8%) | |
| Total | 709 (100%) | |