Table 1. Qualitative and quantitative aspects of included studies (author, year, country, study type and demographics).

NS = Not Specified

Author	Year	Country	Type of study	Sample Size	Male (%)	Female (%)	Mean age (years)
Degner et al. [10]	2004	Germany	Retrospective Cohort	4750	NS	NS	NS
Jung et al. [11]	2011	Korea	Retrospective Cohort	76	23.7	62.4	52.9
Grover et al. [12]	2014	India	Case-control	15	53.8	46.2	66.8
Leth-Møller et al. [13]	2016	Denmark	Retrospective Cohort	26003	44	56	49
Bavbek et al. [14]	2006	Turkey	Case report	1	0	100	67
Cheah et al. [15]	2008	Australia	Case series	2	50	50	70
Ladino et al. [16]	2006	USA	Case report	1	100	0	72
Roxanas et al. [17]	2003	Australia	Case report	1	0	100	86
Famularo et al. [18]	2009	Italy	Case report	1	0	100	76
Ghosh et al. [19]	2014	India	Case report	1	0	100	46