Table 5. Risk of bias assessment.

Study	Patient selection	Index test	Reference standard	Flow and timing	Risk of bias
Beer, Rösler & Hess (1995)	L	L	L	L	L
Caramia et al. (2004)	U	H	H	H	H
Cruz-Martínez et al. (2000)	U	L	L	U	U
Facchetti et al. (1997)	H	L	L	L	H
Hess et al. (1987)	H	H	H	H	H
Jung et al. (2006)	H	U	U	L	H
Kale et al. (2009)	H	U	U	L	H
Kale, Agaoglu & Tanik (2010)	H	U	U	L	H
Kandler et al. (1991)	H	U	U	H	H
Leocani et al. (2006)	H	L	L	L	H
Magistris et al. (1999)	L	U	U	L	U
Mayr et al. (1991)	H	U	U	L	H
Pisa et al. (2020)	H	U	U	L	H
Ravnborg et al. (1992)	L	L	L	L	L
Schmierer et al. (2000)	H	U	U	L	H
Schmierer et al. (2002)	H	U	U	H	H
Tataroglu et al. (2003)	H	U	U	U	H

Note:

H, high; L, low; U, unclear. See ref: (Whiting et al., 2011).