Table 7 Risk of bias in the included studies
Study | Random sequence generation (selection bias) | Allocation concealment (selection bias) | Blinding of participants and personnel (performance bias) | Blinding of outcome assessment (detection bias) | Incomplete outcome data (attrition bias) | Selective reporting (reporting bias) | Other bias |
|---|---|---|---|---|---|---|---|
Korobelnik et al. 2014 [17] | + | ? | + | + | – | – | + |
Brown et al. 2013 [19] | + | ? | + | + | – | – | + |
Boyer et al. 2012 [18] | + | ? | + | ? | – | – | + |
Wittstrom et al. 2012 [16] | ? | ? | ? | ? | + | + | + |
Campochiaro et al. 2008 [27] | – | ? | + | ? | – | – | + |
Asano et al. 2007 [20] | – | – | – | – | – | + | + |
Ramezani et al. 2006 [21] | – | – | – | – | – | – | + |
Jonas et al. 2005 [26] | – | – | – | – | – | – | + |
Tabatabaii et al. 2008 [23] | – | – | – | – | + | + | + |
Parodi et al. 2007 [22] | + | + | ? | ? | + | + | + |
Feltgen et al. 2007 [24] | – | – | – | – | + | + | + |
Mirshahi et al. 2005 [25] | – | – | – | – | + | + | + |
Hayreh et al. 2011 [28] | – | – | – | – | + | + | + |