Faught 1994.

Study characteristics
Patient Sampling	Patients from 2 non‐invasive vascular laboratories affiliated with the Southern Illinois University School of Medicine. Did not specify recruitment. Exclusion criteria: inadequate arteriograms and patients with ICA occlusions
Patient characteristics and setting	77% of the patients included were symptomatic; no other characteristics described
Index tests	DUS Image production: quote "Duplex examinations were performed with a QUAD I Angiodynograph (Quantum Medical Systems, Issaquah, Wash.) until the latter part of 1989, after which the Quantum 2000 (Quantum Medical Systerns)". Contrast: No Criteria used to determine grade of stenosis: ROC curve analysis
Target condition and reference standard(s)	Reference standard: DSA Target condition: suspected carotid disease patients Criteria used to determine grade of stenosis: NASCET Complications: Not described
Flow and timing	Arteriograms were performed within 1 month.
Comparative
Methods	Study design: Unclear whether prospective design. Unclear whether consecutive recruitment Study location: Chicago, USA Year and language of publication: Published in 1994 in English Study period: from January 1, 1989 through October 30, 1992 Participants enrolled: 405 patients Carotids included in analyses: 770 arteries
Notes
Methodological quality
Item	Authors' judgement	Risk of bias	Applicability concerns
DOMAIN 1: Patient Selection
Was a consecutive or random sample of patients enrolled?	Unclear
Was a case‐control design avoided?	Yes
Did the study avoid inappropriate exclusions?	Unclear
Could the selection of patients have introduced bias?		Unclear risk
Are there concerns that the included patients and setting do not match the review question?			Unclear
DOMAIN 2: Index Test (All tests)
Were the index test results interpreted without knowledge of the results of the reference standard?	Yes
If a threshold was used, was it pre‐specified?	No
Could the conduct or interpretation of the index test have introduced bias?		Low risk
Are there concerns that the index test, its conduct, or interpretation differ from the review question?			Low concern
DOMAIN 3: Reference Standard
Is the reference standards likely to correctly classify the target condition?	Yes
Were the reference standard results interpreted without knowledge of the results of the index tests?	Yes
Could the reference standard, its conduct, or its interpretation have introduced bias?		Low risk
Are there concerns that the target condition as defined by the reference standard does not match the question?			Low concern
DOMAIN 4: Flow and Timing
Was there an appropriate interval between index test and reference standard?	Yes
Did all patients receive the same reference standard?	Yes
Were all patients included in the analysis?	Yes
Could the patient flow have introduced bias?		Low risk