Table 3.

Risk of Bias for Included Studies Assessing the Diagnostic Value of Biomarkers for pNETs in MEN1

		Risk of Bias				Applicability
Authors, Year	Biomarker	Patient Selection	Index Test	Reference Standard	Flow and Timing	Patient Selection	Index Test	Reference Standard
de Laat et al., 2013 [12]	CgA, PP, glucagon	+	+	?	−	+	+	+
Qui et al., 2016 [11]	CgA, PP, glucagon, gastrin	−	+	?	−	+	+	+
Granberg et al., 1999 [24]	CgA	−	+	−	−	+	+	−
Mutch et al., 1997 [29]	PP	−	+	−	−	−	+	+
Nehar et al., 2004 [25]	CgA	−	−	+	−	−	+	+
Perrachi et al., 2003 [26]	CgA	−	−	?	?	−	+	?
Langer et al., 2001 [30]	Meal stimulation test	−	+	−	−	−	+	−
Lewis et al., 2012 [28]	PP, gastrin, glucagon	−	+	+	?	−	−	+
Stridsberg et al., 1995 [27]	CgA	−	−	+	?	?	+	+

Abbreviations: +, low risk/low applicability concerns; −, high risk/high applicability concerns; ?, unclear.