Table II.

Risk of bias in included studies.

Study	Random sequence generation	Allocation concealment	Blinding of participants and personnel	Blinding of outcome assessment	Incomplete outcome data	Selective reporting	Other bias
Cepeda et al (25)	Unclear risk	Unclear risk	High risk	High risk	Low risk	Unclear risk	Unclear risk
Koch et al (23)	Unclear risk	Unclear risk	High risk	High risk	Low risk	Unclear risk	Unclear risk
Yilmaz et al (26)	Unclear risk	Unclear risk	High risk	High risk	Low risk	Unclear risk	High risk
Marsdin et al (22)	Unclear risk	Unclear risk	High risk	High risk	Low risk	Unclear risk	Unclear risk
Akbas et al (27)	Unclear risk	Unclear risk	High risk	High risk	Low risk	Unclear risk	Low risk
Karalar et al (28)	High risk	Unclear risk	High risk	High risk	Low risk	Unclear risk	Unclear risk
Cakmak et al (29)	Unclear risk	Unclear risk	High risk	High risk	Low risk	Unclear risk	Low risk
Jurado et al (30)	Low risk	Unclear risk	High risk	Low risk	Low risk	Unclear risk	Unclear risk
Gezginci et al (31)	Low risk	Unclear risk	High risk	High risk	Low risk	Low risk	Low risk
El-Khoury et al (32)	Low risk	Unclear risk	High risk	High risk	Low risk	Unclear risk	Unclear risk
Çift et al (24)	Low risk	Low risk	High risk	Low risk	Low risk	Unclear risk	Low risk