Table 2 Risk of bias of included studies
Study, Year | Randomization process | Bias due to deviations from intended interventions | Bias due to missing data | Bias in measurement of outcomes | Bias in selection of the reported result |
|---|---|---|---|---|---|
Brehm, 2009 [30] | Some concerns | Some concerns | Low risk of bias | Low risk of bias | Some concerns |
Toobert, 2003 [31] | Some concerns | Some concerns | Low risk of bias | Some concerns | Some concerns |
Elhayany, 2010 [17] | Some concerns | Some concerns | High risk of bias | Low risk of bias | Some concerns |
Maiorion, 2016 [32] | Low risk of bias | Some concerns | Low risk of bias | Low risk of bias | Some concerns |
Maryam, 2020 [19] | Some concerns | Some concerns | Low risk of bias | Some concerns | Some concerns |
Alonso-DomÃnguez, 2019 [33] | Low risk of bias | Some concerns | Some concerns | Low risk of bias | Some concerns |
Toobert, 2011 [34] | Low risk of bias | Some concerns | High risk of bias | Low risk of bias | Some concerns |