Table 3 Risk of bias assessment for included studies
Author (year); Country | Â | ||||||
|---|---|---|---|---|---|---|---|
Randomized controlled trials | Selection bias | Performance bias | Detection bias | Attrition bias | Reporting bias | Other bias | |
de Jonghe (2014); The Netherlands [29] | Low | Low | Low | High | Low | Low | |
Nickkholgh (2011); Germany [32] | Low | Low | High | Low | Unclear | Unclear | |
Sultan (2010); Egypt [33] | Unclear | Low | Unclear | Unclear | Low | Low | |
Yamaguchi (2014); Japan [34] | Unclear | Unclear | Unclear | Unclear | Low | Unclear | |
Observational studies | Bias due to confounding | Bias in selection of participants into the study | Bias in classification of interventions | Bias due to deviations from intended interventions | Bias due to missing data | Bias in measurement of outcomes | Bias in selection of the reported results |
Artemiou (2015); Slovakia [30] | Moderate | Low | Low | Low | Low | Moderate | Low |
Miyata (2017); Japan [31] | Moderate | No information | Low | Low | Low | Low | Low |