Table 2 The demographic characteristics of the recruited sample at baseline

Age - Mean (SD), y^b

68.9

(7.35)

68.9

(7.78)

68.8

(6.96)

0.963

 Male

22

(15.6)

12

(16.9)

10

(14.3)

0.669

 Female

119

(84.4)

59

(83.1)

60

(85.7)

Body mass index - Mean (SD), kg/m^2b

25.2

(3.48)

25.0

(3.45)

25.4

(3.51)

0.565

Symptom duration - Mean (SD), y

6.4

(8.52)

6.7

(9.39)

6.0

(7.60)

0.664

Level of education^a

0.524

 Primary school or less

22

(15.6)

12

(16.9)

10

(14.3)

 Junior high school

48

(34.0)

25

(35.2)

23

(32.9)

 High school

31

(22.0)

12

(16.9)

19

(27.1)

 College graduate and above

40

(28.4)

22

(31.0)

18

(25.7)

Marital status^a

0.669

 Single

22

(15.6)

12

(16.9)

10

(14.3)

 Married

119

(84.4)

59

(83.1)

60

(85.7)

Number of affected knees ^a

0.207

 One

63

(44.7)

28

(39.4)

35

(50.0)

 Two

78

(55.3)

43

(60.6)

35

(50.0)

Uses a walker^a

0.637

 Yes

5

(3.5)

2

(2.8)

3

(4.3)

 No

136

(96.5)

69

(97.2)

67

(95.7)

 Hypertension

0.553

  Yes

68

(48.2)

36

(50.7)

32

(45.7)

  No

73

(51.8)

35

(49.3)

38

(54.3)

 Diabetes

0.560

  Yes

29

(20.6)

16

(22.5)

13

(18.6)

  No

112

(79.4)

55

(77.5)

57

(81.4)

 Coronary heart disease

0.743

  Yes

38

(27.0)

20

(28.2)

18

(25.7)

  No

103

(73.0)

51

(71.8)

52

(74.3)

 Osteoporosis

0.105

  Yes

21

(14.9)

14

(19.7)

7

(10.0)

  No

120

(85.1)

57

(80.3)

63

(90.0)

 Analgesics

0.654

  Yes

32

(22.7)

15

(21.1)

17

(24.3)

  No

109

(77.3)

56

(78.9)

53

(75.7)

 Cartilage protection drugs

0.067

  Yes

29

(20.6)

19

(26.8)

10

(14.3)

  No

112

(79.4)

52

(73.2)

60

(85.7)