Table 1.
QUADAS and scoring guide for each of the 5 schemes
QUADAS Item | Scoring scheme | |||||
1 | 2 | 3 | 4 | 5 | ||
1 | Was the spectrum of patients representative of the patients who will receive the test in practice? | 1 | 2 | 2 | 3 | 10 |
2 | Were selection criteria clearly described? | 1 | 2 | 1 | 1 | 2 |
3 | Is the reference standard likely to correctly classify the target condition? | 1 | 2 | 3 | 2 | 10 |
4 | Is the time period between reference standard and index test short enough to be reasonably sure that the target condition did not change between the two tests? | 1 | 2 | 3 | 1 | 6 |
5 | Did the whole sample or a random selection of the sample, receive verification using a reference standard of diagnosis? | 1 | 2 | 3 | 3 | 9 |
6 | Did patients receive the same reference standard regardless of the index test result? | 1 | 2 | 3 | 2 | 7 |
7 | Was the reference standard independent of the index test (i.e. the index test did not form part of the reference standard)? | 1 | 2 | 3 | 1 | 7 |
8 | Was the execution of the index test described in sufficient detail to permit replication of the test? | 1 | 2 | 2 | 1 | 3 |
9 | Was the execution of the reference standard described in sufficient detail to permit its replication? | 1 | 2 | 2 | 1 | 2 |
10 | Were the index test results interpreted without knowledge of the results of the reference standard? | 1 | 2 | 3 | 3 | 8 |
11 | Were the reference standard results interpreted without knowledge of the results of the index test? | 1 | 2 | 3 | 3 | 6 |
12 | Were the same clinical data available when test results were interpreted as would be available when the test is used in practice? | 1 | 2 | 3 | 3 | 5 |
13 | Were uninterpretable/ intermediate test results reported? | 1 | 2 | 1 | 1 | 4 |
14 | Were withdrawals from the study explained? | 1 | 2 | 1 | 1 | 3 |
Total score | 14 | 28 | 33 | 26 | 85 |
All scoring given above refer to the score which studies that answered "yes" to each question should be given. Studies that answered "no" or "unclear" were scored 0 for each scoring system with the exception of system 2 in which studies that scored "unclear" were given 1.