Table 1 Demographic characteristics of the study participants

Gender

Male

47

48.3

43.7

4.647

0.031

Female

53

51.7

56.3

Immigrant

Yes

1.2

1.2

1.0

0.190

0.663

No

98.8

98.8

99

Age group (years)

5 – 15

20

21.7

15.7

45.64

<0.001

16 – 30

19.3

21.4

14.3

31 – 45

34.3

33.2

37

46 – 65

25.4

22.9

31.7

≥66

1.0

0.8

1.3

Ethnicity

Han

73.2

95.7

16.6

N/A

<0.001 ^a

Bai

26.4

3.8

83.2

Other

0.4

0.5

0.2

Occupation

Farmer

78.6

76.8

83

N/A

<0.001 ^a

Fisherman

0.4

0.5

0.1

Herdsman

0.2

0.3

0

Worker

0

0.1

0

Student

20.1

21.8

15.8

Pre-school

0.3

0.4

0.1

Business

0.2

0

0.8

Government

0.1

0.1

0

Other

0.1

0.1

0.1

Education

Illiterate

12.2

10.6

16.3

N/A

<0.001 ^a

Primary school

48.9

48.2

50.6

Junior high school

34.4

36.6

28.9

Senior high school

3.9

4.1

3.3

College and above

0.6

0.5

0.8