TABLE 2.

Quality assessment.

Study	Random sequence generation	Allocation concealment	Selective reporting	Other sources of bias	Blinding (participants and personnel)	Blinding (outcome assessment)	Incomplete outcome data	General quality
El‐Sayed (2011)	L	L	H	L	L	U	L	Moderate
Moradi et al. (2012)	L	H	H	H	H	H	L	Low
Rafiee Vardanjani et al. (2013)	L	H	H	H	L	U	L	Low
Farzanegi (2014)	L	H	H	H	H	H	L	Low
Fakoori Jouibari et al. (2014)	L	H	H	H	L	U	L	Low
Zakizadeh et al. (2015)	L	H	H	L	H	H	L	Low
Esmaillzadeh et al. (2015)	L	L	H	L	H	H	L	Low
Adelnia Najafabadi et al. (2015)	L	L	H	L	L	H	L	Low
Dehghan et al. (2016)	L	H	H	H	L	U	L	Low
Wainstein et al. (2016)	L	L	L	L	L	U	L
Marjan Bedakhanian et al. (2017)	L	L	H	H	H	H	L	Low
Gheflati et al. (2019)	L	L	H	L	H	H	L	Low
Ghorbanian et al. (2019)	L	H	H	H	H	H	L	Low
Papoli et al., 2019)	L	L	H	L	H	H	L	Low
Darvish Damavandi et al., 2021)	L	L	H	L	L	U	L	Moderate
Delvarianzadeh et al., 2021)	L	H	H	H	L	U	L	Low

Abbreviations: H, high‐risk of bias; L, low‐risk of bias; U, unclear‐risk of bias.