Table 1.

Quality assessment of the 21 included diagnostic studies

Study	Risk of bias				Applicability concerns
	Patient selection	Index test	Reference standard	Flow and timing	Patient selection	Index test	Reference standard
Kumar et al.	+	+	+	+	+	+	+
Aydin et al.	−	−	+	−	+	+	+
Koo et al.	−	+	+	+	+	+	+
Ibrahiem et al.	+	+	+	+	+	+	+
Kim et al.	−	+	+	+	−	+	+
Yamamura et al.	+	−	+	?	+	+	+
Girometti et al.	−	?	+	+	+	+	+
Selnæs et al.	−	−	+	−	+	+	+
Portalez et al.	−	?	+	+	−	+	+
Tamada et al.	−	+	+	+	+	+	+
Rinaldi et al.	−	?	+	−	+	+	+
Yagci et al.	+	+	+	+	+	+	+
Weidner et al.	+	+	+	?	+	+	+
Kim et al.	−	−	+	+	+	+	+
Chen et al.	+	+	+	?	+	+	+
Iwazawa et al.	+	+	+	+	+	+	+
Miao et al.	+	+	+	+	+	+	+
Isebaert et al.	−	+	+	+	+	+	+
Vilanova et al.	+	+	+	−	+	+	+
Peng et al.	−	−	+	+	+	+	+
Lim et al.	−	+	+	+	+	+	+

+ low risk, − high risk, ? unclear risk