Table 2. Risk of bias summary.

Authors	Adequate sequence generation	Allocation concealment	Blinding participant and personal	Blinding outcome assessment	Incomplete outcome data	Selective outcome report	Other source of bias
Stark et al. (2021)	L	L	L	U	L	L	L
Cockayne et al. (2021)	L	L	H	H	L	L	L
Chu et al. (2017)	L	L	L	L	L	U	H
Kamei et al. (2015)	L	H	H	H	L	L	H
Pighills et al. (2011)	L	H	H	L	L	L	H
La Grow et al. (2006)	U	L	U	H	H	H	H
Campbell et al. (2005)	U	L	U	H	H	H	H
Nikolaus & Bach (2003)	L	L	H	H	L	L	L
Pardessus et al. (2002)	U	H	H	H	U	U	L
Stevens et al. (2001)	L	L	H	L	L	L	H
Gerson, Camargo Jr & Wilber (2005)	H	H	H	H	L	U	L
Cumming et al. (1999)	L	U	H	L	U	L	H