Table 2 The methodological quality of the included studies
Author, year | 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 |
|---|---|---|---|---|---|---|---|
Callway et al. 2010 | − | + | + | − | − | − | − |
Oostdam et al. 2012 | − | + | + | − | + | − | − |
Barakat et al. 2013 | − | + | + | − | + | − | − |
Seneviratne et al. 2015 | − | − | + | − | − | − | − |
Simmons et al. 2018 | − | − | + | − | − | − | − |
Wang et al. 2017 | − | ? | + | − | + | − | − |
Krohn Garnæs1 et al. 2018 | − | ? | + | − | + | − | − |
Daly et al. 2018 | − | − | + | − | + | − | − |