Spencer 2008.
| Clinical features and settings | Routine screening | |
| Participants | 622 participants: 55 cases and 567 controls matched for gestational age Denmark ‐ screening programme Dates not reported Pregnant women Median maternal age cases 35.8 years, controls 29.3 years 8‐13 weeks' gestation (results modelled on only cases where testing conducted before 10 weeks' gestation) |
|
| Study design | Case‐control study | |
| Target condition and reference standard(s) | Down's syndrome: 55 cases (31 tested before 10 weeks' gestation) Reference standards: karyotyping or follow‐up to birth |
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| Index and comparator tests | Maternal age First trimester NT (details not reported) Fresh serum samples tested for: First trimester PAPP‐A and free ßhCG (Kryptor analyser, Brahms) Frozen samples tested for: First trimester ADAM 12 (measured blind to clinical outcome) (manual DELFIA assay, PerkinElmer Life & Analytical Sciences) |
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| Follow‐up | Details not reported | |
| Aim of study | To establish the effectiveness or otherwise of ADAM 12 as an early screening marker | |
| Notes | ||
| Table of Methodological Quality | ||
| Item | Authors' judgement | Description |
| Representative spectrum? All tests | Yes | Routine screening of typical pregnant population |
| Acceptable reference standard? All tests | Yes | Karyotyping or follow‐up to birth |
| Partial verification avoided? All tests | Yes | All women received a reference standard |
| Differential verification avoided? All tests | No | Choice of reference standard depended on index test results |
| Incorporation avoided? All tests | Yes | Reference standard was independent of the index test |
| Reference standard results blinded? All tests | No | Reference standard interpreted with knowledge of index test results |
| Index test results blinded? All tests | Yes | Index test interpreted without knowledge of reference standard results |
| Relevant clinical information? All tests | Yes | Information available as would be in standard clinical practice |
| Uninterpretable results reported? All tests | No | No details given for test failures/uninterpretable measurements |
| Withdrawals explained? All tests | No | No details of withdrawals given |