Table 1 Socio-demographic characteristics

Gender

 Male

398

86.3

 Female

63

13.7

Age (years)

 ≤ 30

35

7.6

 31–40

122

26.5

 41–50

192

41.6

 50–60

78

16.9

 ≥ 60

34

7.4

Level of education

 Primary school and lower

222

48.1

 Junior high school

154

33.4

 High school

55

11.9

 College and higher

3

0.7

 Unavailable

27

5.9

Marital status

 Never married

262

56.8

 Married

119

25.8

 Cohabited

7

1.5

 Widowed

8

1.8

 Divorced

53

11.6

 Separated

6

1.3

 Unavailable

6

1.3

Ethnicity

 Han

438

95.0

 Others

23

5.0

Residence

 Rural

406

88.1

 Urban

54

11.7

 Unavailable

1

0.2

Living status

 Alone

65

14.1

 In a dormitory with others

7

1.5

 Under supervision

1

0.2

 With parents or siblings

248

53.8

 With spouse or children

106

23.0

 With remote relatives

1

0.2

 Others

3

0.7

 Unavailable

30

6.5

Employment status

 Unemployed

254

55.1

 Employed

177

38.4

 Unavailable

30

6.5