Table 2.

Risk of bias for the randomized controlled trials.

Reference	Q1a	Q2b	Q3c	Q4d	Q5e	Q6f	Q7g	Q8h	Q9i	Q10j	Q11k	Q12l	Q13m	Quality grade
Nahm et al (2019) [36]	Un	U	Yo	U	U	Y	Y	Y	Y	Y	Y	Y	Y	B
De Main et al (2022) [37]	U	U	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	Y	B

^aQ1: true randomization.

^bQ2: allocation concealment.

^cQ3: similar at baseline.

^dQ4: blinding of subjects.

^eQ5: blinding of the researcher.

^fQ6: blinding of outcome assessors.

^gQ7: identical treatment other than the intervention.

^hQ8: follow-up description.

ⁱQ9: intention-to-analysis.

^jQ10: the same outcome measurement.

^kQ11: reliability of outcome measurements.

^lQ12: appropriate statistical analysis.

^mQ13: appropriate trial design.

ⁿY: yes.

^oU: unclear.