Table 1.
Sociodemographic characteristics of respondents
| Characteristics | N | % |
| Gender | ||
| Male | 1614 | 45.6 |
| Female | 1927 | 54.4 |
| Age (years) | ||
| 18–24 | 359 | 10.1 |
| 25–44 | 1882 | 53.2 |
| 45–64 | 994 | 28.1 |
| >64 | 282 | 8.6 |
| Education | ||
| Secondary education or below | 1325 | 37.4 |
| High school education | 740 | 20.9 |
| College or above | 1476 | 41.7 |
| Residency | ||
| Urban | 2277 | 64.3 |
| Rural | 1264 | 35.7 |
| Region | ||
| Beijing | 988 | 27.9 |
| Heilongjiang | 862 | 24.3 |
| Guangdong | 811 | 22.9 |
| Sichuan | 880 | 24.9 |
| Monthly household income (¥) | ||
| 0–3499 | 987 | 27.9 |
| 3500+ | 2554 | 72.1 |
| Marital status | ||
| Married | 2803 | 79.2 |
| Not married | 738 | 20.8 |