Zannetti 2000.

Clinical features and settings	People who underwent EVAR. Type of stents received: "The AneuRxstent graft was employed in 144 procedures, the Gore Excluder in 9 procedures, and the Talent graft in one." Aneurysm diameter: mean (± SD) AAA diameter: 50.2 ± 8.3 mm. Setting: unit of vascular surgery.
Participants	108 participants; mean (± SD) age: 70.1 ± 6.7 years; ASA IV: n = 19 (19%); Eurostar classification A: n = 18 (17%); B: n = 62 (61%); C: n = 7 (7%); D: n = 7 (7%); E: n= 8 (8%). Comorbidities: not reported. Geography: Italy.
Study design	Consecutively enrolled participants. "After surgery, patients were entered in a follow‐up protocol consisting of colour‐duplex and CT scan examinations scheduled at 1, 6, 12 months after surgery, and every 6 months thereafter. Mean follow up of the study cohort was 8.5 months."
Target condition and reference standard(s)	Target condition: endoleak. Definition of endoleak: flow "outside the endograft and within the aneurysmal sac." Endoleak (absolute n): 12. Prevalence of endoleak: 37.5% (12/32). Reference standard: contrast‐enhanced CT. Image acquisition: contrast‐enhanced CT scan performed with 5‐mm slices in 162 (82%) studies and with 3‐mm thick slices in balance, from above SMA to level of origin of common femoral artery. Spiral (78) or axial CT (120) scans obtained at different time intervals according to study protocol. Spiral CT acquired with collimation 5 mm, table speed 5 mm, pitch 1. Type of CT scanner: not reported. Use of contrast: mean 140 mL of iso‐osmotic, non‐ionic iodinated contrast media injected 25 s before imaging acquisition.
Index and comparator tests	Index test: CDUS. Image production: "The scanhead was applied in both the transverse and longitudinal views to obtain colour and Doppler optimisation. The entire AAA sac, proximal and distal necks, the aorta, iliac and femoral arteries were systematically imaged and measurements were performed on both sagittal and transverse views. The presence of perigraft endoleaks was suspected when a reproducible colour signal outside the endograft and within the aneurysmal sac was visualised. All suspected endoleaks were further evaluated with the Doppler signal to avoid colour artefacts." Type of US: C4‐2‐MHz curved array transducer (ATL 3000 HDI system, Advanced Technology Laboratory). Use of contrast: no. Operator: 2 ("All duplex scan examinations were performed by two vascular surgeons with the same machine (ATL HDI).")
Follow‐up	"Compliance with the study protocol was not achieved in 51 patients for different reasons including perioperative death (two patients), conversion to open repair (four patients), duplex scan performed in a different centre in patients from out of town and refusal. Three patients (2%) were excluded from the study protocol because of inadequate duplex visualisation of the abdominal aortic aneurysm (AAA) sac due to obesity or intestinal gas."
Notes	198 concurrent all duplex‐scan examinations performed.
Table of Methodological Quality
Item	Authors' judgement	Description
Representative spectrum? All tests	Yes	Consecutive participants who received EVAR received both index test and reference standard.
Acceptable reference standard? All tests	Yes	Reference standard was CT scan.
Acceptable delay between tests? All tests	Unclear	Not reported.
Partial verification avoided? All tests	Yes	All study participants accounted for and results of reference standard reported for all.
Differential verification avoided? All tests	Yes	All participants who received index test subjected to same reference standard.
Incorporation avoided? All tests	Yes	Index test not part of reference standard.
Reference standard results blinded? All tests	Yes	"The interpretation of all colour‐duplex and CT scans was blinded to all concurrent and prior studies."
Index test results blinded? All tests	Yes	"The interpretation of all colour‐duplex and CT scans was blinded to all concurrent and prior studies."
Relevant clinical information? All tests	Yes	Yes.
Uninterpretable results reported? All tests	Yes	"With respect to the presence of endoleak, CT and colour‐duplex scans were conflicting in 4 cases (2%). In detail, duplex scan failed to show one endoleak (1 false negative) and revealed 3 endoleaks not confirmed by CT examination (3 false positives). Digital subtraction angiography performed on these 4 patients revealed the absence of endoleak in all cases. With respect to type of endoleak, of the 11 endoleaks detected both by CT and colour‐duplex scan, there was discordance in 2 cases. Based on the 2 colour duplex‐scan examinations, reperfusion of the aneurysmal sac appeared in continuity with the inferior mesenteric artery and the 2 endoleaks were classified as non‐graft‐related. Inversely, in these 2 patients CT scan revealed accumulation of the majority of contrast media in the area of the proximal implant zone, suggesting the presence of a graft‐related endoleak in accordance with digital subtraction angiography obtained subsequently."
Withdrawals explained? All tests	Yes	"Compliance with the study protocol was not achieved in 51 patients for different reasons including perioperative death (two patients), conversion to open repair (four patients), duplex scan performed in a different centre in patients from out of town and refusal. Three patients (2%) were excluded from the study protocol because of inadequate duplex visualisation of the abdominal aortic aneurysm (AAA) sac due to obesity or intestinal gas."

2D: two‐dimensional; 3D: three‐dimensional; 4D: four‐dimensional; AAA: abdominal aortic aneurysm; ASA: American Society of Anesthesiology; BMI: body mass index; CCDS: colour‐coded duplex sonography; CDI: colour Doppler imaging; CDUS: colour duplex ultrasound; CE‐CDUS: contrast‐enhanced colour duplex ultrasound; CEUS: contrast‐enhanced ultrasound; CFD: colour flow duplex; CI: confidence interval; CPS: contrast pulse sequences; CT: computed tomography; CTA: computed tomography angiography; DSA: digital subtraction angiography; DUS: duplex ultrasound; DUSS: duplex ultrasound sonography; erAAA: emergency abdominal aortic aneurysm; EVAR: endovascular aneurysm repair; GPS: global positioning system; IV: intravenous; LDCE: low‐dose contrast‐enhanced; MRA: magnetic resonance angiography; MS‐CT: multi‐slice computer tomography; n: number of participants; s: second; SD: standard deviation; SMA: superior mesenteric artery; US: ultrasound.