Table 3 Comparison of patient baseline characteristics of participants reporting at least one period of significant pain variability potential flare

Female gender

53

56

Age (years): mean (SD)

63.6 (8.2)

67.4 (8.7)

Employed

27

17

Attended full time education after school

17

13

Married/cohabiting

76

68

Current smoker

11

10

Body Mass Index (kg/m²): mean (SD)

30.0 (5.3)

28.7 (4.8)

Routine/manual occupational class^a

48

56

PF-10 physical function subscale (0–100): mean (SD)

56.1 (27.9)

58.7 (30.1)

WOMAC knee pain (0–20): mean (SD)

6.5 (4.2)

5.6 (4.3)

WOMAC knee function (0–68): mean (SD)

21.1 (14.3)

18.5 (14.7)

HADS Anxiety (0–21): mean (SD)

6.8 (4.1)

6.3 (4.0)

HADS Depression (0–21): mean (SD)

4.8 (3.4)

4.2 (3.1)

 Normal

33

31

 Isolated tibiofemoral

5

3

 Isolated patellofemoral

23

25

 Combined tibiofemoral and patellofemoral

40

41

 Normal

33

31

 Mild

28

30

 Moderate/severe

39

39

 None

67

66

 Mild

23

23

 Moderate/gross

10

11

 Nodal symptomatic hand OA

15

18

 None

65

71

 Unilateral

26

23

 Bilateral

9

5

  < 12 months

8

16

 1 year to < 5 years

36

35

 5 years to < 10 years

21

19

  ≥ 10 years

35

30

 None

35

46

≤30 min

60

50

>30 min

6

4

Knee given way during past month

32

27

Seen hospital doctor about knee

27

20

Frequent sedentary activity

11

8

Frequent moderate activity

54

55

Frequent vigorous activity

28

28