Table 3. Evaluation of the methodological quality of the included studies.

Studies	Random Sequence Generation	Allocation Concealment	Blind	Incomplete Outcome Data	Selective Reporting	Other Sources of Bias
Bhansali et al. 2017 [21]	Random allocation software	Unclear	Double blind	Complete	Low risk	Unclear
Carlsson et al. 2015 [12]	Sealed envelopes	Yes	Open	Complete	Low risk	None
Chen et al. 2016 [22]	Randomization table	Unclear	Unclear	Complete	Low risk	Unclear
Hu et al. 2013 [23]	Randomized blocks	Unclear	Double blind	1 patient withdrawed	Low risk	None
Hu et al. 2016 [24]	Balanced permuted-block randomization method	Unclear	Unclear	Complete	Low risk	Unclear
Zhang et al. 2016 [25]	Unclear	Unclear	Unclear	Complete	Low risk	Unclear
Zhou et al. 2013 [26]	Unclear	Unclear	Unclear	Complete	Low risk	Unclear