Table 1 The demographics of participants

Age (years)

 <30

480

14.9

 30~

2158

67.0

 45~

585

18.2

Years of sexual active life

 <15

1692

52.4

 > = 15

1534

47.6

Number of sexual partners

 0-1

2853

97.7

 2-3

64

2.2

 >3

3

0.1

Educational level

 Elementary school and below (%)

350

9.6

 Junior middle school (%)

1368

43.1

 High school (%)

1008

31.8

 College and above (%)

490

15.5