Table 2.
The study quality of the included studies assessed by the Cochrane collaboration tool.
| Study | Year | Random sequence generation | Allocation concealment | Blinding of participants | Blinding of outcome assessment | Follow-up ≥80% | Free of selective reporting | Free of other bias |
|---|---|---|---|---|---|---|---|---|
| Wojtowicz JC | 2011 | ? | ? | + | ? | + | + | + |
| Barabino S Manuel Neuzimar | 2003 | + | ? | + | + | + | + | + |
| Pinheiro Jr | 2007 | ? | + | + | ? | + | ? | − |
| Haleh Kangari | 2013 | + | + | + | + | + | + | + |
| Nikki Heidi Ong | 2013 | ? | + | + | ? | + | ? | ? |
| Andrea Oleñik | 2013 | ? | ? | + | + | + | ? | + |
| Kawakita T | 2013 | ? | ? | + | + | + | ? | + |
+, Adequate (low risk of bias); ?, unclear (unknown risk of bias); −, inadequate (high risk of bias).