Cuckle 1995b.

Clinical features and settings	High‐risk referral for invasive testing and testing for bacterial analysis.
Participants	315 participants. UK. Dates not specified. Pregnant women: 24 cases undergoing invasive testing and 294 controls undergoing testing for bacterial analysis 11‐23 weeks' gestation.
Study design	Case‐control study.
Target condition and reference standard(s)	Down's syndrome: 24 cases. Reference standards: amniocentesis or CVS for cases and follow‐up for controls.
Index and comparator tests	Urinary beta core fragment (Modified radioimmunoassay method). Urinary total oestrogen (continuous flow reaction based on the Kuber method).
Follow‐up	No details given of methods of follow‐up.
Aim of study	To evaluate the use of multiple urinary markers rather than serum in order to screen for Down's syndrome.
Notes
Table of Methodological Quality
Item	Authors' judgement	Description
Representative spectrum? All tests	Yes	Selective testing of high‐risk women as done in practice.
Acceptable reference standard? All tests	Yes	Karyotyping or follow‐up to birth.
Partial verification avoided? All tests	Yes	All women had a reference standard.
Differential verification avoided? All tests	No	Women had different reference standards.
Incorporation avoided? All tests	Yes	Reference standard was independent of the index test.
Reference standard results blinded? All tests	Yes	Reference standard interpreted without 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.