Table 1 Socio-demographic and Personal characteristics of the study participants, China, 2018–2020 (n = 57,501)

 Men

37,240

64.8

 Women

20,261

35.2

 <25

12,085

21.0

 25-

26,139

45.5

 35-

12,301

21.4

 45-

5802

10.1

 55-

1174

2.0

 <2

16,061

27.9

 2-

12,072

21.0

 4-

7299

12.7

 6-

9717

16.9

 8-

12,352

21.5

 Junior high school

15,369

26.7

 Senior high school

21,901

38.1

 University degree

19,231

33

 Graduate degree

1000

1.7

 Single

20,997

36.5

 Married

35,343

61.5

 Divorced/Widowed

1161

2.0

 <18.5

6006

10.4

 18.5-

39,328

68.4

 25-

12,167

21.2

 No

36,527

63.5

 Occasionally

10,111

17.6

 Frequently

10,863

18.9