Study	Reason for exclusion
Bannowsky 2008	Inappropriate assessment of outcome (not fair comparison at the time of outcome assessment)
Bannowsky 2010	Inappropriate assessment of outcomes (not fair comparison at the time of outcome assessment)
Bannowsky 2012	Inappropriate assessment of outcomes (not fair comparison at the time of outcome assessment)
Brock 2003	Inappropriate assessment of outcome (not fair comparison at the time of outcome assessment)
Canat 2015	Inappropriate assessment of outcome (not fair comparison at the time of outcome assessment)
Cavallini 2005	Inappropriate assessment of outcome (not fair comparison at the time of outcome assessment)
Chambers 2015	Wrong intervention
Engel 2011	Inappropriate assessment of outcomes (not fair comparison at the time of outcome assessment)
Fode 2014	Wrong intervention
Kim 2017	Inappropriate assessment of outcomes (not fair comparison at the time of outcome assessment)
Kohler 2007	Inappropriate assessment of outcomes (not fair comparison at the time of outcome assessment)
Kosev 2013	Wrong study design
McCullough 2008	Inappropriate assessment of outcomes (not fair comparison at the time of outcome assessment)
Montorsi 1997	Inappropriate assessment of outcomes (not fair comparison at the time of outcome assessment)
Montorsi 2004	Inappropriate assessment of outcome (not fair comparison at the time of outcome assessment)
Mulhall 2013	Inappropriate assessment of outcomes (not fair comparison at the time of outcome assessment)
Naccarato 2016	Inappropriate assessment of outcomes (not fair comparison at the time of outcome assessment)
Nehra 2005	Inappropriate assessment of outcome (not fair comparison at the time of outcome assessment)
Raina 2007	Wrong study design
Seo 2014	Wrong study design (retrospective study)
Yassin 2010	Incorrect reference