Table 2.

Quality assessment of included studies (Newcastle-Ottawa Scale).

Study	Selection	Comparability	Outcome
Giuliante et al. 2009 [22]	4	1	3
Hamady et al. 2006 [23]	4	2	3
Jamison et al. 1997 [24]	4	2	3
Minagawa et al. 2000 [25]	4	1	3
Scheele et al. 1995 [26]	4	2	3
Shimizu et al. 2007 [27]	4	1	3
Tomlinson et al. 2007 [28]	4	2	3
Wanebo et al. 1996 [29]	4	2	3