TABLE 2.

Cochrane risk-of-bias.

	Randomization bias (selection bias)	Allocation concealment (selection bias)	Blinding of participants and personnel (performance bias)	Blinding of outcome assessment (detection bias)	Incomplete outcome data (attrition bias)	Selective reporting (reporting bias)	Other bias
Yörükoğlu et al. (21)	“+”	“+”	“+”	“+”	“+”	“–”	?
Yu et al. (24)	“+”	“–”	“–”	“–”	“+”	“+”	?
Zhang et al. (15)	“+”	“+”	“+”	?	“+”	“+”	?
Ciftci et al. (14)	“–”	“–”	“–”	?	“–”	“+”	?
Singh et al. (22)	“+”	“–”	“–”	“–”	“+”	“+”	?
Yayik et al. (26)	“+”	“+”	“–”	“+”	“+”	“–”	?
Goel et al. (25)	“+”	“–”	“+”	“+”	“–”	“–”	?
Finnerty et al. (27)	“+”	“–”	?	“–”	“–”	“–”	?
Yeşiltaş et al. (23)	“+”	“+”	“+”	“+”	“+”	“–”	?
Zhu et al. (39)	“+”	“+”	“–”	“+”	“+”	?	?

“+” – low risk of Bias (green).

“–” – high risk of bias (red).

? – undetermined (yellow).