“…After application of critical search strategies and exclusion criteria, 11 follow-up studies (Moullan et al, 2003;Chang-Claude et al, 2005;Brem et al, 2006;Giotopoulos et al, 2007;Chang-Claude et al, 2009;Zhou et al, 2010;Zschenker et al, 2010;Mangoni et al, 2011;Falvo et al, 2012;Raabe et al, 2012;Terrazzino et al, 2012) comprising 2199 cases were eligible for the present analysis. The baseline characteristics of the included studies are shown in Table 1.…”