Study Q1 Q2 Q3 Q4 Q5 Q6 Q7 Q8 Q9 Total
(% score yes) 		Methodological
quality
Al-Ahmad et al. [24] Yes Yes Yes Yes Yes Yes Yes Yes No 88 High
de Freitas, et al. [25] Yes Yes Yes No Yes Yes Yes Yes No 77 High
Giordano et al. [26] Yes Yes No No No Yes Yes Yes No 66 Moderate
Zaugg et al. [27] Yes Yes No No No Yes Yes Yes No 55 Moderate
Herrmann et al. [28] Yes Yes Yes No Yes Yes Yes Yes No 77 High

Total = ΣY/applicable items (the not applicable items were excluded from the sum). Methodological quality was categorized as low when the study reaches up to 49% score "yes", moderate when the study reached 50% to 69% score "yes", and high when the study reached more than 70% score "yes".