FIND 2020c (CH).

Study characteristics
Patient Sampling	Single‐group study to estimate sensitivity and specificity at single site; this extraction is for data from Switzerland (see FIND 2020c (BR) and FIND 2020c (DE) for extraction of data from other sites): patients seeking COVID‐19 testing at main testing centre; described as presenting either with symptoms compatible with a SARS‐CoV2 infection, or with a known positive contact or asymptomatic HCWs (n = 529; from total cohort of 1064 volunteers) Recruitment: consecutive recruitment Prospective or retrospective: prospective
Patient characteristics and setting	Setting: community (main testing centre) Location: Hopitaux Universitaires de Geneve (HUG), Geneva Country: Switzerland Dates: 9‐23 October 2020 Symptoms and severity: not stated; time pso recorded for 183/191, 96% 141/183 COVID positive cases had symptoms for 0‐4 days (77%) Demographics: not stated Exposure history: not stated
Index tests	Test name: STANDARD Q COVID‐19 Ag (09COV30D) Manufacturer: SD Biosensor Inc Antibody: not reported Ag target: not reported Test method: rapid chromatographic immunoassay in lateral flow format Samples used: NP Transport media: proprietary swab/media provided by SD Biosensor Sample storage: author contact advises tested as soon as possible and within the time limit specified in the IFU Test operator: HCW Definition of test positivity: presence of visible control and test lines Blinding reported: yes Timing of samples: median not reported (range 0‐15); day < 0‐3, 122, 67%; day 4‐7, 54, 29%; day 8+; 7, 34%
Target condition and reference standard(s)	Reference standard: RT‐PCR Roche Cobas; Ct threshold < 40 (from Figure) Definition of non‐COVID cases: same as for cases. Single negative PCR required for absence of infection Genetic target(s): not stated Samples used: NP swab (paired, from contralateral nostril) Timing of reference standard: not stated; author contact advises only paired swabs used Blinded to index test: yes Incorporated index test: no
Flow and timing	Time interval between index and reference tests: paired swabs; 0 to several days based on PCR turnaround times at the lab All participants received same reference standard: yes Missing data: reports 0 missing data Uninterpretable results: none reported Indeterminate results (index test): none reported Indeterminate results (reference standard): none reported Unit of analysis: participant
Comparative
Notes	Funding: FIND Publication status: published Source: FIND/HUG websites/IFU index test Author COI: none stated (these are independent evaluations)
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 inclusions?	Yes
Could the selection of patients have introduced bias?		Low risk
Are there concerns that the included patients and setting do not match the review question?			Low concern
DOMAIN 2: Index Test (Evaluations of single test application)
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?	Yes
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 2: Index Test (Evaluations of serial (repeat) testing)
DOMAIN 3: Reference Standard
Is the reference standards likely to correctly classify the target condition?	No
Were the reference standard results interpreted without knowledge of the results of the index tests?	Yes
Reference standard does not incorporate result of index test?	Yes
Could the reference standard, its conduct, or its interpretation have introduced bias?		High risk
Are there concerns that the target condition as defined by the reference standard does not match the question?			High
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
Did all participants receive a reference standard?	Yes
Could the patient flow have introduced bias?		Low risk