Enrico Martin

140 Chapter 6 Quality assessment The Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2 tool) is the current research standard for evaluation of studies validating diagnostic tests and was used to rate study quality of all diagnostic studies included in this review (Table X1). The results of the QUADAS-2 tool indicate risk of bias and applicability concerns for the following categories: patient selection, index test, reference standard and flow and timing (risk of bias only). This study used a modified QUADAS-2 tool using categorical questions adjusted to study design of the included studies (Table X2). The full QUADAS-2 tool can be found on the QUADAS website (www.quadas.org ).