Table 1. Analysis of the methodological quality of the studies.

Author	Q1	Q2	Q3	Q4	Q5	Q6	Q7	Q8	Q9	Q10	Q11	Q12	Q13	TOTAL
Lazarus et al.(23)	Unclear	Unclear	Yes	No	NA	Unclear	Yes	No	Unclear	Yes	Yes	Yes	Yes	6
Clark(24)	Yes	Unclear	Yes	No	NA	Unclear	Yes	Yes	Yes	Yes	Yes	Yes	Yes	9
Ieto et al.(13)	Unclear	Unclear	Yes	No	NA	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes	9
Park et al.(15)	Yes	Yes	Yes	No	NA	Yes	Yes	No	Unclear	Yes	Yes	Yes	Yes	9
Byeon(16)	Yes	Unclear	Yes	No	NA	Unclear	Yes	No	Unclear	Yes	Yes	Yes	Yes	7
Diaféria et al.(14)	Unclear	Unclear	Yes	No	NA	Yes	No	Yes	No	Yes	No	Yes	Yes	6
Kim et al.(17)	Yes	Unclear	Yes	No	NA	Unclear	Yes	Yes	Yes	Yes	Yes	Yes	Yes	9
Byeon(18)	Unclear	Unclear	Yes	No	NA	Unclear	Yes	No	Unclear	Yes	Yes	Yes	Yes	6
Van den Steen et al.(26)	Unclear	Unclear	Yes	No	NA	Unclear	Yes	Yes	Yes	Yes	Yes	Yes	Yes	8
Hsiang et al.(25)	Yes	Unclear	Yes	No	NA	Yes	Yes	Yes	Yes	Yes	No	Yes	Yes	9
Park et al.(19)	Yes	Yes	Yes	Yes	NA	Yes	Yes	Yes	No	Yes	Yes	Yes	Yes	11
Park et al.(20)	Yes	Unclear	Yes	No	NA	Yes	Yes	Unclear	Unclear	Yes	Yes	Yes	Yes	8
Park et al.(21)	Unclear	Unclear	Yes	No	NA	Unclear	Yes	Yes	Yes	Yes	Yes	Yes	Yes	8
Lee et al.(22)	Unclear	Unclear	Yes	No	NA	Unclear	Yes	Yes	No	Yes	Yes	Yes	Yes	7

Caption: NA = Not Applicable; Q1 = Was true randomization used for assignment of participants to treatment groups?; Q2 = Was allocation to treatment groups concealed?; Q3 = Were treatment groups similar at the baseline?; Q4 = Were participants blind to treatment assignment?; Q5 = Were those delivering treatment blind to treatment assignment?; Q6 = Were outcomes assessors blind to treatment assignment?; Q7 = Were treatment groups treated identically other than the intervention of interest?; Q8 = Was follow up complete and if not, were differences between groups in terms of their follow up adequately described and analyzed?; Q9 = Were participants analyzed in the groups to which they were randomized?; Q10 = Were outcomes measured in the same way for treatment groups?; Q11 = Were outcomes measured in a reliable way?; Q12 = Was appropriate statistical analysis used?; Q13 = Was the trial design appropriate, and any deviations from the standard RCT design (individual randomization, parallel groups) accounted for in the conduct and analysis of the trial?