Table 1. Demographic characteristics of medical students (N = 1878).
| Characteristics | Frequency | Percentage |
| Age (years) a | ||
| 17–19 | 260 | 14.2 |
| 20–22 | 1379 | 75.4 |
| 23–25 | 191 | 10.4 |
| Gender b | ||
| Male | 595 | 32.1 |
| Female | 1260 | 67.9 |
| Ethnic groups c | ||
| Han | 1697 | 91.8 |
| Other | 151 | 8.2 |
| Grade | ||
| 1 | 243 | 12.9 |
| 2 | 679 | 36.2 |
| 3 | 695 | 37 |
| 4 | 204 | 10.9 |
| 5 | 57 | 3 |
| Major | ||
| Clinical | 823 | 43.8 |
| Non-clinical | 1055 | 56.2 |
| Clinical internship | ||
| Yes | 280 | 14.9 |
| No | 1598 | 85.1 |
| Attitude towards premarital sexual behavior d | ||
| Positive | 276 | 15.2 |
| Negative | 435 | 24 |
| Neutral | 927 | 51 |
| Undecided | 178 | 9.8 |
| Previous sexual behavior e | ||
| Yes | 150 | 8.3 |
| No | 1661 | 91.7 |
a,b,c,d,e
Data were missing for 48, 23, 30, 62 and 67 students, respectively.