Table 1.

Assessment of methodological quality

Allocation concealment	Low risk of bias	Randomization method would not allow investigator/participant to know or influence the intervention group before the eligible participant entered in the study.
	Unclear	Randomization stated but no information on the method used was available.
	High risk of bias	Methods of randomization used such as alternate medical record numbers or unsealed envelopes; any information in the study indicating that investigators or participants could influence the intervention group.
Blinding	Adequate	Blind to investigators, participants, outcome assessors, and data analysts.
	Inadequate	The treatment group could be identified in > 20% of participants due to side effects of treatment.
Incomplete outcome data	Low risk of bias	Specifically reported by authors that intention-to-treat analysis was undertaken; this was confirmed at the study assessment stage. If the analysis was not clearly stated but it was confirmed at the study assessment stage, it would also be granted a judgment of “Yes.”
	Inadequate	If the analysis was not clearly stated, or if it was stated but there was no confirmation that it had taken place at the study assessment stage, it would also be judged as “inadequate.”
	High risk of bias	No intention-to-treat analysis was reported with no confirmation at the study assessment stage.