Table 2 Results of intention to treat analysis. Outcome scores and mean changes and 95% confidence intervals (CI) unless stated otherwise at the different follow-ups

Sickness absence – days off work (SD)^*

N/A

N/A

47.52 (4.77)

(38.33,56.71)

50.92 (5.26)

(40.58,61.26)

3.40

(-10.43,17.24)

26.15 (3.69)

(18.91,33.40)

27.15

(18.96,35.85)

1.25

(-9.87,12.38)

No. sick listed

105 (30.2%)

102 (34.7%)

60 (23.2%)

52 (23.4%)

46 (16.2%)

39 (16.2%)

Change

-104

-102

2

8

7

Disability (RMQ) ^a

8.36 (6.93)

7.52 (6.87)

5.80 (6.93)

5.73 (7.19)

5.77 (7.35)

5.56 (6.70)

Change

-5.86

(-6.52,-5.19)

- 6.64

(-7.35,-5.94)

0.79

(-0.15,1.72)

-8.31

(-9.00,-7.61)

-8.53

(-9.26,-7.80)

0.23

(-0.2,1.2)

-8.43

(-9.10,-7.77)

- 8.76

(-9.46,-8.06)

0.33

(-0.6,1.2)

Pain (LBP-NRS) ^b

18.96 (13.82)

19.93 (13.24)

18.39 (14.26)

19.48 (14.03)

17.32 (13.74)

18.69 (13.86)

Change

-9.82

(-11.15,-8.50)

-9.24

(-10.71,-7.76)

-0.58

(-2.49,1.32)

-9.91

(-11.32,-8.49)

-9.50

(-11.10,-7.92)

-0.41

(-2.48,1.6)

-11.14

(-12.57,-9.71)

-9.96

(-11.5,-8.35)

-1.19

(-3.27,0.89)

Health related QoL (physical, PCS)^c

59.94 (12.87)

59.81 (11.65)

60.46 (14.28)

58.64 (11.09)

63.17 (13.70)

63.09 (12.42)

Change

10.42

(9.16,11.68)

9.55

(8.05,11.04)

0.87

(-1.05,2.80)

11.61

(9.12,14.10)

11.66

(9.17,14.16)

-0.05

(-3.56,3.45)

13.19

(11.77,14.61)

12.54

(10.91,14.17)

0.65

(-1.47,2.78)

Health related QoL (mental, MCS)^d

52.48 (10.26)

51.46 (10.46)

53.94 (9.18)

49.94 (10.72)

54.21 (8.94)

52.92 (9.11)

Change

2.17

(1.09,3.25)

1.79

(0.52,3.05)

0.38

(-1.18,1.94)

3.31

(0.85,5.77)

2.25

(-0.22,4.70)

1.06

(-2.34,4.47)

3.75

(2.67,4.82)

2.71

(1.50,3.92)

1.03

(-0.43;2.50)

Mental health (SCL-90)^e

GSI

0.61 (0.60)

0.67 (0.59)

0.67 (0.71)

0.76 (0.62)

0.51 (0.55)

0.69 (0.54)

Change

-0.12

(-0.17,-0.07)

-0.11

(-0.16,-0.05)

-0.01

(-0.09,0.06)

-0.50

(-0.18,-0.08)

-0.18

(-0.30,-0.05)

0.13

(-0.05,0.30)

-0.13

(-0.35,0.09)

-0.16

(-0.33,0.01)

0.03

(-0.24,0.31)

Depression^f

(SCL-90 subscale)

0.87 (0.85)

0.94 (0.85)

0.88 (0.99)

1.07 (0.82)

0.68 (0.71)

0.94 (0.81)

Change

-0.18

(-0.25,-0.10)

-0.16

(-0.24,0.08)

-0.01

(-0.12,0.01)

-0.22

(-0.42,-0.03)

-0.22

(-0.42,-0.03)

-0.001

(-0.28,0.27)

-0.33

(-0.60,-0.06)

-0.21

(-0.42,0.01)

-0.12

(-0.47,0.23)

Somatization^g

(SCL-90 subscale)

0.89 (0.67)

0.92 (0.63)

0.96 (0.73)

1.03 (0.67)

0.96 (0.82)

1.07 (0.67)

Change

-0.22

(-0.28,-0.17)

-0.26

(-0.32,-0.19)

0.03

(-0.05,0.12)

-0.23

(-0.37,-0.09)

-0.35

(-0.49,-0.21)

0.12

(-0.08,0.32)

-0.21

(-0.44,0.0)

-0.24

(-0.42,-0.06)

0.03

(-0.27,0.32)

Fear Avoidance, physical activity (FAB-PA)^h

13.01 (6.38)

12.71 (5.91)

13.97 (5.93)

(n = 39)

14.10 (5.90) (n = 49)

13.12 (6.70)

(n = 17)

11.93 (6.46) (n = 28)

Change

-2.28

(-3.23,-1.92)

-2.52

(-3.27,-1.76)

-0.10

(-1.02,0.90)

-1.92

(-3.40,-0.44)

-2.11

(-3.54,-0.69)

0.19

(-1.84,2.22)

-2.28

(-4.46,-0.11)

-3.64

(-5.46,-1.82)

1.34

(-1.49,4.19)

Fear avoidance,

work (FAB-W) ⁱ

18.97 (12.99)

19.50 (13.18)

20.65 (12.94) (n = 40)

21.02 (12.19) (n = 46)

16.81 (10.62) (n = 15)

17.57 (12.46) (n = 28)

Change

-3.70

(-4.70,-2.71)

-2.99

(-4.14,1.89)

-0.71

(-2.22,0.79)

-1,57

(-3.89,0.75)

-5.62

(-7.99,-3.30)

4.05

(0.78,7.33)

-4.15

(-8.59,0.30)

-6.75

(-10.28,-3.21)

2.60

(-3.07,8.27)