Ramirez 2005.

Study characteristics
Patient sampling	Cross‐sectional cohort (screening cohort + surveillance cohort); prospective single‐centre study.
Patient characteristics and setting	Participants: 30 participants (11 for screening, 19 for surveillance). Mean age 54.4 years, range 43 to 69 years. 30 (100%) men. Outpatients only. Baseline diagnosis: cirrhosis. Aetiology: 14 HCV, 8 alcohol, 7 alcohol + HCV; 1 cryptogenic. Disease severity: mean MELD score 12.5; mean Child‐Pugh score 6.3. Co‐morbidity: not available. Geographical location of the study: USA. Inclusion criteria: cirrhosis. People scheduled for oesophago‐gastro‐duodenoscopy for screening or surveillance of oesophageal varice. Exclusion criteria: not available.
Index tests	Index test: string wireless capsule endoscopy (device was modified attaching a string to control movement up and down the oesophagus). Criteria for oesophageal varices: other classification, adequately described and logically defined. Operator: 1 experienced endoscopist, but no information about experience with index test. Blinded from the reference standard.
Target condition and reference standard(s)	Target condition: oesophageal varices. Reference standard: oesophago‐gastro‐duodenoscopy. Criteria for oesophageal varices: other classification, adequately described and logically defined. Prevalence of the target condition: 83% (25/30 participants).
Flow and timing	Reference standard and index test timing: variable. 20 participants were at the same day, 3 within 24 hours, 2 within 14 days, 1 within 1 month, 4 after 1 month.
Comparative
Notes	Observer variation: no data on observer variation were reported. Uninterpretable results: uninterpretable results were not reported. Side effects or complications: data on side effects or complications were reported. The string wireless capsule was deemed to be easy or mildly difficult to swallow by 79.3% (23/29) of participants, moderately difficult by 17.2% (5/29), very difficult by 3.5% (1/29). Pulling the string capsule out of the oesophagus caused no or minimal discomfort in 82.8% (24/29) and moderate discomfort in 17.2% (5/29). 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?	Unclear
		Low	Low
DOMAIN 4: Flow and Timing
Was there an appropriate interval between index test and reference standard?	No
Did all patients receive the same reference standard?	Yes
Were all patients included in the analysis?	Yes
		High