“Quality Assessment of Diagnostic Accuracy Studies” (QUADAS) Tool.

Y = yes; N = no; U = unclear;
§reference standard included sequencing and pyrosequencing; LC: lung cancer.
Items: 1) Was the spectrum of patients representative of the patients who will receive the test in practice? 2) Were the selection criteria clearly described? 3) Is the reference standard likely to classify the target condition correctly? 6) Did patients receive the same reference standard regardless of the index test result? 8) Was the execution of the index test described in sufficient detail to permit replication of the test? 9) Was the execution of the reference standard described in sufficient detail to permit replication? 10) Were the index test results interpreted without knowledge of the results of the reference standard result? 11) Were the reference standard results interpreted without knowledge of the results of the index test? 13) Were uninterpretable/intermediate test results reported? 14) Were withdrawals from the study explained?