Studies | Year | Selection bias | Performance bias | Detection bias | Attrition bias | Reporting bias | Other bias | |
---|---|---|---|---|---|---|---|---|
 |  | Random sequence generation | Allocation concealment | Blinding of participants and personnel | Blinding of outcome assessment | Incomplete outcome data | Selective reporting | Anything else, ideally prespecified |
Bogner et al. [26] | 2012 | U | U | H | U | L | U | U |
Bogner et al. [27] | 2010 | U | U | H | U | L | U | U |
Ciechanowski et al. [31] | 2006 | L | U | H | L | L | L | U |
Ell et al. [32] | 2011 | L | L | H | L | L | L | U |
Katon et al. [19] | 2010 | U | L | H | L | U | L | U |
Katon et al. [23] | 2004 | L | L | H | L | U | L | U |
Kinder et al. [33] | 2006 | U | U | H | U | L | L | U |
Williams Jr et al. [28] | 2004 | L | L | H | L | L | L | U |