AbuRahma 2005.

Clinical features and settings	178 participants treated with aortic stent grafts for AAA. Type of stents received: 86 Ancure (Guidant Corporation, USA), 55 AneuRx (Medtronic,USA), and 37 Excluder (WL Gore & Associates, USA). Aneurysm diameter: not reported. Setting: vascular laboratory.
Participants	156 men; mean age: 74 years; range: 49‐89 years. Comorbidities: not reported. Geography: USA.
Study design	Cross‐sectional study; participants were consecutively enrolled; all participants were without the target condition at the start of study.
Target condition and reference standard(s)	Target condition: endoleak. Definition of endoleak: "An endoleak was determined using CT scans based on extravasation of contrast between the prosthesis and the aneurysm wall; by CDUS, endoleak was indicated by flow and spectral signals outside the prosthesis. Primary or early endoleak occurred within 30 days of the procedure; late endoleak referred to leaks observed beyond 30 days postoperatively." Endoleak (absolute n): 34. Prevalence of endoleak: 9.3% (34/367). Reference standard: helical CT imaging. Image acquisition: non‐contrasted and contrasted axial images of the abdominal aorta, 3D multiple rotational projections and sagittal and coronal views; from 1 cm above celiac trunk to femoral bifurcation; thickness: 3 mm. Type of CT scanner: Philips Medical Systems, Inc (Shelton, CT, USA). Use of contrast: Optiray 350 (125 mL; Mallinkrodt Medical, USA).
Index and comparator tests	Index test: CDUS. Image production: transverse and anteroposterior images obtained from level of suprarenal aorta above graft to distal iliac or femoral arteries. Type of US: HDI 5000 scanner, ATL‐Philips, USA. Use of contrast: no. Operator: registered vascular technologist and board‐certified vascular surgeon.
Follow‐up	No loss to follow‐up, missing data, or adverse events.
Notes	Secondary objective: to compare pre‐ and postoperative maximal aneurysm diameters. Study conducted between February 2000 and October 2004. Endoleaks, 26 (14.6%) early and 8 (4.5%) late; the 26 early endoleaks included 11 (6.2%) type I, 13 (7.3%) type II, and 2 (1.1%) type IV endoleaks; the 8 late endoleaks after 30 days included 5 (2.7%) type I and 3 (1.6%) type II. Follow‐up protocol for serial CT and CDUS scans at 1 month and every 6 months thereafter. Overall mean follow‐up: 16 months, range: 1‐53 months.
Table of Methodological Quality
Item	Authors' judgement	Description
Representative spectrum? All tests	Yes	Participants consecutively enrolled.
Acceptable reference standard? All tests	Yes	Reference standard was CT scan.
Acceptable delay between tests? All tests	Yes	"CT and CDUS scans were considered concurrent if they were done within 7 days."
Partial verification avoided? All tests	Yes	Appeared all participants that received both tests.
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	Reference standard performed before CDUS.
Index test results blinded? All tests	Yes	"Neither the registered vascular technologist nor the reviewing surgeon was aware of the CT results during any portion of the CDUS examination."
Relevant clinical information? All tests	Yes	Yes.
Uninterpretable results reported? All tests	Yes	No apparent uninterpretable data ("no delayed imaging was performed to detect questionable endoleaks").
Withdrawals explained? All tests	Yes	No explicit report concerning loss to follow‐up, missing data, or adverse events.