Table 3.

Risk of bias assessment for included randomized controlled clinical trails

First author (publication year)	Random sequence generation	Allocation concealment	Blinding of participants and personnel	Blinding of outcome assessment	Incomplete outcome data	Selective reporting
Abdollahzad (2015)	+	+	+	+	+	?
Rahmani (2018)	+	?	+	?	+	?
Fallah (2018)	+	+	+	-	+	?
Gholami (2018)	?	?	+	+	-	?
Attar (2015)	+	?	-	-	+	?
Zhang (2018)	+	+	+	+	+	?
Mori (2009)	+	+	-	-	+	?
Henriksen (1999)	?	+	-	-	+	?
Moazen (2015)	+	+	+	-	+	?
Ericsson (1999)	?	?	-	-	+	?
Dai (2011)	+	+	+	+	+	?
Farsi (2016)	?	?	-	-	+	?
Mohseni (2015)	+	+	+	+	+	?
Jafarvand (2016)	?	?	-	-	+	?
Gholnari (2018)	+	+	+	-	+	?
Hodgson (2002)	?	?	-	-	+	?
Izadi (2018)	+	+	+	-	+	?
Shojaei (2011)	+	?	-	-	+	?
Nadjarzadeh (2011)	?	?	-	-	+	?
Raygan (2016)	+	+	+	-	+	?