Table 3 Summary of assessment of risk of bias for accepted randomized controlled trials based on Scottish Intercollegiate Guidelines Network (SIGN) criteria [35]

Bergman et al., 2004 [40]

Y

CS

Y

Y

N^b

Y

Y

12 weeks (immediately post-intervention)

Y

CS

UC = 14 %

MT + UC = 13 %

26 weeks:

UC = 11 %

UC + MT = 9 %

52 weeks:

UC = 13 %

MT + UC = 6 %

Cook et al., 2014 [41]

Y

Y

N

Y

Y

CS

Y

Post-intervention:

N

CS

Manipulation: 2/38 = 5 %

Control: 4/36 = 11 %

Cleland et al., 2013 [42]

Y

Y

Y

Y

Y

N

Y

1 month:

Y

CS

MTEX: 3/37 = 8 %

HEP: 2/37 = 5 %