*3.3. Risk of Publication Bias*

The results found in the assessment of the risk of publication bias from the included studies are summarized in Figure 2. In general, all the studies satisfied the seven domains of bias defined by Cochrane Collaboration. All the included articles had a focused issue and all the patients who entered the trial were properly accounted for at its conclusion. Aside from the experimental intervention, both the control and intervention groups were treated equally, and all clinically important outcomes were considered. The randomization process was applied in the three articles that were also double-blinded.

**Figure 2.** Results of risk of bias assessment regarding the methodological quality of included studies ((**A**) Risk of bias summary: review authors' judgments about each risk of bias item for each included study; (**B**) Risk of bias graph: review authors' judgments about each risk of bias item presented as percentages across all included studies).
