Table 1 General Characteristics of WCA by CHNS Rounds, 1991–20,151−2

Sample(N)

3730

2866

3623

-

Education level (%)

Primary school/below

51.6 (0.8)

35.2 (0.9)

18.1 (0.7)

< 0.001

Middle school

32.1(0.8)

36.1(0.9)

37.4(0.9)

High school/above

16.3 (0.6)

28.7(0.8)

44.5 (0.9))

Marital status (%)

Single

23.8(0.7)

14.2(0.7)

11.50.6)

< 0.001

Married

76.2(0.7)

85.8(0.7)

88.5(0.6)

Income (1k yuan)

3.8 (0.1)

8.9 (0.2)

44.8 (1.4)

< 0.001

BMI (kg/m²)

21.8(0.1)

22.8(0.1)

23.5 (0.1)

< 0.001

PA(METs/w)

462.6 (4.6)

246.0(4.0)

166.6(2.8)

< 0.001

Smoking (%)

2.0(0.1)

2.7(0.1)

3.0 (0.1)

0.507

Drinking (%)

12.0 (0.6)

9.3(0.7)

7.2(0.7)

< 0.001

Region (%)

Urban

14.1(0.6)

13.9(0.6)

22.9 (0.7)

< 0.001

Rural

85.9(0.6)

86.1(0.6)

77.1(0.7)

District (%)

Eastern

35.8(0.8)

44.7(0.9)

46.0(1.0)

< 0.001

Central

38.2(0.8)

33.3(0.9)

26.0(0.8)

Western

26.0(0.7)

22.0(0.8)

28.0(0.9)