Kozlowski 2007 PC.
| Clinical features and settings | Routine referral | |
| Participants | 3862 participants with complete outcome data Germany ‐ tertiary level prenatal centres January 2000 ‐ December 2003 Pregnant women Median maternal age 34 years (range 14‐46 years), 43.2% ≥ 35 years 11‐14 weeks' gestation |
|
| Study design | Cohort study | |
| Target condition and reference standard(s) | Down's syndrome: 26 cases Reference standard: karyotyping or follow‐up to birth |
|
| Index and comparator tests | Maternal age First trimester NT (FMF certified sonographers) First trimester free ßhCG and PAPP‐A (Kryptor analyser, Brahms) Risk cut‐point 1:300 |
|
| Follow‐up | Data on pregnancy outcome were obtained by contacting the patient or their general gynaecologist. Women without complete outcome data (8%) were excluded from the study | |
| Aim of study | To evaluate and compare the screening performance for fetal trisomy 21 in the first trimester of pregnancy in general gynaecologists practices and specialised centres for prenatal care in Germany | |
| 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 | Yes | 146 women (including 11 with down's syndrome) excluded as results could not be assigned to gynaecologists' or prenatal centre group |