de Franchis 2008.

Study characteristics
Patient sampling	Cross‐sectional cohort study (screening cohort + surveillance cohort). Prospective, multicentre study with 11 centres.
Patient characteristics and setting	Participants: 288 participants (screening cohort: 195 participants; surveillance cohort: 93 participants); mean 56 years, range 21 to 81 years. Sex: not available. Baseline diagnosis: cirrhosis. Aetiology: 20% alcohol, 8.9% HBV, 35.0% HCV, 13.3% alcohol + HBV or HCV cirrhosis, 22.8% other (Budd‐Chiari syndrome, portal vein thrombosis, etc.). Disease severity: Child‐Pugh score A 68.8%; Child‐Pugh score B 25.4%; Child‐Pugh score C 5.8%. Co‐morbidity: not available. Geographical location of the study: Italy, Spain, USA, and Israel. Inclusion criteria: ≥ aged 18 years. Signs/symptoms of portal hypertension, without previous diagnosis of oesophageal varices, with clinical indication for screening endoscopy for the detection of varices, or with prior endoscopic diagnosis of oesophageal varices and indication for surveillance endoscopy. Exclusion criteria: dysphagia, Zenker's diverticulum, previous endoscopic treatment of oesophageal varices, known or suspected intestinal obstruction, cardiac pacemakers or other implanted electro‐medical devices, pregnancy, planned magnetic resonance imaging examination within 7 days after ingestion of the capsule, prior abdominal surgery of the gastrointestinal tract (other than uncomplicated appendectomy or uncomplicated cholecystectomy), any condition that precluded compliance with study or device instructions (or both), life‐threatening conditions and current participation in another clinical study.
Index tests	Index test: capsule endoscopy (PillCam ESO, Given Imaging, Ltd., Yoqneam, Israel). Criteria for oesophageal varices: small varices occupying < 25% of the circumference and large varices occupying > 25%. Operator: experienced capsule endoscopist, blinded from the reference standard.
Target condition and reference standard(s)	Target condition: any oesophageal and large oesophageal varices. Reference standard: oesophago‐gastro‐duodenoscopy. Criteria for oesophageal varices: other classification, adequately described and logically defined. Prevalence of the target condition: 63% (180/288 participants). 79 with large oesophageal varices.
Flow and timing	2 participants were withdrawn from the study. 1 due to "loss of capsule endoscopy recording" and 1 for unsuspected oesophageal stricture.
Comparative
Notes	Observer variation: no data on observer variation reported. Uninterpretable results: data were reported. Side effects or complications: side effects or complications: overall, 4 (1.4%) adverse events were reported within the study. 1 episode of severe pain occurred with oesophago‐gastro‐duodenoscopy and improved within 1 week. 3 adverse events occurred with the capsule: 1 episode of diarrhoea that resolved spontaneously within 24 hours, 1 episode of nausea with capsule retention due to an unsuspected oesophageal stricture requiring removal of the capsule by oesophago‐gastro‐duodenoscopy, and 1 episode of vomiting caused by capsule retention due to an unsuspected oesophageal stricture (the capsule was passed by mouth by vomiting). Type of publication: full text.
Methodological quality
Item	Authors' judgement	Risk of bias	Applicability concerns
DOMAIN 1: Patient Selection
Was a consecutive or random sample of patients enrolled?	Yes
Was a case‐control design avoided?	Yes
Did the study avoid inappropriate exclusions?	Yes
Did the study enrol only patients with suspected oesophageal varices not until diagnosed?	No
		High	Low
DOMAIN 2: Index Test All tests
Were the index test results interpreted without knowledge of the results of the reference standard?	Yes
		Low	Low
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
		Low	Low
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
		Low