Table 3.

Assessment of Quality of Studies

	selection				comparability	outcome
References	1	2	3	4	5	6	7	8	score
2011 Kumagai et al.	b*	a*	a*	a*	a b **	a*	a*	a*	9
2013 Inokuchi et al.	b*	a*	a*	a*	a *	a*	a*	c	7
2007 Nunobe et al.	b*	a*	a*	a*	b *	a*	a*	a*	8
2008 Kojima et al.	b*	a*	a*	a*	a b **	a*	a*	a*	9
2010 Namikawa et al.	b*	a*	a*	a*	a b *	a*	a*	a*	8
2011 Kang et al.	b*	a*	a*	a*	a *	a*	a*	c	7
2011 Tanaka et al.	b*	a*	a*	a*	a b *	a*	a*	c	7
2012 Lee et al.	b*	a*	a*	a*	a b **	a*	a*	a*	9
2014 An et al.	b*	a*	a*	a*	a *	a*	a*	a*	8
2014 Shim et al.	b*	a*	a*	a*	a *	a*	a*	a*	8
2015 Komatsu et al.	b*	a*	a*	a*	b *	a*	a*	a*	8
2016 Imamura et al.	b*	a*	a*	a*	a b **	a*	a*	c	8
2016 Tran et al.	b*	a*	a*	a*	a b **	a*	a*	a*	9
2017 Edoardo et al.	b*	b	a*	a*	a b *	a*	a*	a*	7