Table 2.
Risk of bias. Cochrane Collaboration’s tool for assessing risk of bias [28].
| Study | Sequence | Allocation | Blinding1 | Blinding2 | Outcome1 | Outcome2 | Other |
|---|---|---|---|---|---|---|---|
| Thien V et al., 2000 [30] | (+) | (+) | (-) | (-) | (+) | (+) | (+) |
| Hart S et al., 2001 [31] | (+) | (+) | (-) | (-) | (-) | (-) | (+) |
| Del Valle MF et al., 2010 [32] | (+) | (+) | (-) | (-) | (+) | (+) | (+) |
| Catalan-Matamoros D et al., 2011 [33] | (+) | (+) | (-) | (-) | (+) | (+) | (+) |
| Fernandez-Del-Valle M et al., 2014; 2015; 2016 [34,35,36] | (+) | (-) | (-) | (-) | (+) | (+) | (+) |
| Hay P et al., 2018 [37] | (+) | (+) | (+) | (+) | (+) | (+) | (-) |
Sequence: random sequence generation; Allocation: allocation concealment; Blinding1: blinding of participants and personnel; Blinding2: blinding of outcome assessment; Outcome1: incomplete outcome data; Outcome2: selective reporting. Other: Design issues or initial imbalance. Low risk (+); High risk (-).