Table 2.

Risk of bias assessment for individual studies (randomized trials).

Study	Bias arising from the randomization process	Bias due to deviations from intended interventions	Bias due to missing outcome data	Bias in measurement of the outcome	Bias in selection of the reported result	Overall bias
Everson et al. [22]	Low risk	Low risk	Low risk	Low risk	Low risk	Low risk
Feld et al. [23]	Some concerns	Low risk	Low risk	Low risk	Low risk	Some concerns
Lai et al. [28]	Some concerns	Low risk	Low risk	Low risk	Low risk	Some concerns