Table 2. Methodology quality of the included RCTs.

Study	Jadad score
	Randomization	Allocation concealment	Blinding	Attrition	Score
Liu 2014	1	0	0	0	1
Chen 2013	2	0	0	0.5	2.5
Jia 2013	1	0	0	0	1
Zhang 2015	1	0	0	0	1
Deng 2013	1	0	0	0	1
Ma 2013	2	0	0	0	2
Zhang 2010	2	0	0	0	2

Note: the Silan Chen paper states that two participants were lost in each group, but because no reasons were given, we gave them a 0.5 score for attrition. RCT, randomized clinical trial.