Cytokines as Early Markers of Colorectal Anastomotic Leakage: A Systematic Review and Meta-Analysis

Table 2

Quality assessment of the included studies by judging risk of bias and applicability using Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2). +: low risk of bias; −: high risk of bias; ?: not specified.

Author	Year	Risk of bias				Applicability
		Patient Selection	Index test	Reference standard	Flow and timing	Patient selection	Index test	Reference standard
Bertram et al. [23]	2003	−	+	−	−	+	+	−
Fouda et al. [21]	2011	−	+	+	−	+	+	+
Herwig et al. [24]	2002	−	+	+	−	+	+	+
Matthiessen et al. [4, 19]	2007	−	+	+	−	+	+	+
Yamamoto et al. [20]	2011	−	+	+	−	+	+	+
Ellebæk et al. [25]	2014	−	+	?	−	+	+	?
Reisinger et al. [26]	2014	−	+	+	−	+	+	+