Table 4: Articles most frequently included in the reviews assessed.

Articles		Salt	Park	Cowden	Swenty	Lartey	Rush	Chen
		2008 a [35]	2010 b [36]	2011 c [32]	2011 d [37]	2013 e [33]	2013 f [34]	2014 g [38]
Owens h [61]	2001	x	x
Beecroft i [62]	2001	x	x
Squires j [63]	2002	x	x
Crimlisk k [64]	2002	x	x
Roche l [65]	2004	x					x
Almada m [39]	2004	x	x				x
Blanzola n [66]	2004		x				x
Marcum o [40]	2004	x	x				x
Altier p [41]	2006	x	x				x
Herdrich q [67]	2006	x	x
Keller r [68]	2006		x				x
Krugman s [42]	2006	x	x				x
Lee t [69]	2009						x	x
Komaratat u [70]	2009						x	x