Table 3.

Risk of the methodological bias score of included studies.

Authors, year	Random sequence generation (selection bias)	Allocation concealment (selection bias)	Binding of participants and personnel (performance bias)	Blinding of outcome assessment (detecting bias)	Incomplete outcome data (attrition bias)	Selective reporting bias (reporting bias)	Other bias
Valizadeh, 2015	U	U	H	U	L	L	H
Li, 2011	L	U	H	H	L	L	U
Bakir, 2018	U	U	U	U	L	L	H
Unal, 2016	U	U	U	U	L	L	H
Zengin, 2018	L	U	U	U	L	L	U
Rambod, 2019	L	L	H	L	L	L	U
Malekshahi, 2018	U	U	U	U	U	L	H
Oshvandi, 2014	L	L	H	U	L	L	U
Samarehfekri, 2020	L	L	U	U	L	L	U
Toygar, 2020	L	U	L	L	L	L	U
Bahrami, 2019	L	L	H	U	L	L	U
Noh et al., 2019	L	U	H	U	L	L	U
Mahdavipour et al., 2019	U	U	H	U	L	L	U
Soheili et al., 2017	L	U	H	U	L	L	U
Vardanjani et al., 2013	L	U	H	U	L	L	H
Bagheri-nesami et al., 2014	L	U	U	U	L	L	U
Khaledifar et al., 2017	U	U	U	U	L	L	H
Saatsaz et al., 2016	L	U	H	U	L	L	H
Pasyar et al., 2018	L	L	H	U	L	L	H
Koras et al., 2019	U	U	H	U	L	L	H
Eguchi et al., 2016	U	U	U	U	L	L	U
Ozturk et al., 2018	L	U	H	U	L	L	U
Ramezanibadr et al., 2018	L	U	H	U	L	L	U
Shahsavari et al., 2017	L	U	H	U	L	L	U
Abbaszadeh et al., 2018	L	L	U	L	L	L	U
Levy et al., 2020	L	U	H	L	L	L	U

H: high risk, L: low risk, U: unclear.