Questions Asked by QUADAS Tool to Assess Quality of Studies Evaluating Diagnostic Tests

Question no.QUADAS tool question
1Was the spectrum of patients representative of the patients who will receive the test in practice?
2Were selection criteria clearly described?
3Is the reference standard likely to correctly classify the target condition?
4Is the time period between reference standard and index test short enough to be reasonably sure that the target condition did not change between the 2 tests?
5Did the whole sample or a random selection of the sample receive verification using a reference standard of diagnosis?
6Did patients receive the same reference standard regardless of the index test result?
7Was the reference standard independent of the index test (i.e., the index test did not form part of the reference standard)?
8Was the execution of the index test described in sufficient detail to permit replication of the test?
9Was the execution of the reference standard described in sufficient detail to permit its replication?
10Were the index test results interpreted without knowledge of the results of the reference standard?
11Were the reference standard results interpreted without knowledge of the results of the index test?
12Were the same clinical data available when test results were interpreted as would be available when the test is used in practice?
13Were uninterpretable/intermediate test results reported?
14Were withdrawals from the study explained?