Table 2

Bias assessment of each study
Author, year Random sequence generation Allocation concealment Blinding of participants and personnel Blinding of outcome assessment Incomplete outcome data addressed Selective reporting
De Greef et al. 2011-1 [24] Low Low Low Low Low Low
De Greef et al. 2010 [25] Low Low Low Low Low Low
Tudor-Locke et al. 2004 [26] Unclear Unclear Low Low High Low
Piette et al. 2011 [27] Low Low Low Low High Low
De Greef et al. 2011-2 [28] Unclear Unclear Low Low Low Low
Kirk et al. 2009 [29] Low Low Low Low Low Low
Plotnikoff et al. 2013 [30] Low Low Low Low High Low
Engel et al. 2006 [31] Unclear Unclear Low Low High Low
Bjørgaas et al. 2008 [18] Unclear Unclear Low Low High Low
Andrews et al. 2011 [32] Low Low Low Low Low Low
Diedrich et al. 2010 [33] Unclear Unclear Low Low High Low

Summary assessments of the risk of bias for each RCT within studies:

Low risk of bias, low risk of bias for all key domains; unclear risk of bias, unclear risk of bias for one or more key domains; high risk of bias, high risk of bias for one or more key domains.

Qiu et al.

Qiu et al. BMC Medicine 2014 12:36   doi:10.1186/1741-7015-12-36

Open Data