Lephart 2020 [A].

Study characteristics
Patient Sampling	Single group study including samples from: [1] patients presenting to emergency department (n=75), or Recruitment: Not stated Prospective or retrospective: Not reported [Study also reports results for second group of recovering inpatients with previously laboratory‐confirmed COVID‐19 (n=13); for purposes of this review only those in group [1] were included]
Patient characteristics and setting	Setting: [1] ED Location: Not stated; pathology lab at University of Michigan Medical School Country: USA Dates: 22 Apr to 5 May 2020 Symptoms and severity: Not reported Demographics: Not reported Exposure history: Not reported
Index tests	Test name: [A] ID NOW (second index test [B] Xpert Xpress, extracted as Lephart 2020 [B]; two additional RT‐PCR tests evaluated in study but not included in this review). No product codes reported Manufacturer: [A] Abbott Molecular Target gene: Not reported in paper Test method: [A] isothermal PCR Samples used: [A] Nasal; Presume collected by HCP but not reported Transport media: [A] None ‐ transported dry swabs in sealed sterile collection bags Sample storage: [A] within 24h Test operator: Not stated; presume lab staff Definition of test positivity: Each assay was performed according to manufacturer’s EUA instructions. Blinding reported: Not stated; unlikely Timing of samples: On presentation; timing pso not reported
Target condition and reference standard(s)	Reference standard: Composite: positive on >=2 of 4 NATs tested considered D+, including [A] ID NOW, [B] Xpert Xpress, [C] Simplexa COVID‐19 Direct (Diasorin) (this was the standard of care assay), [D] RealTime m2000 SARS‐CoV‐2 Assay (Abbott Molecular) Definition of non‐COVID cases: Three negatives (on different assays) required for D‐ Genetic target(s): Not stated Samples used: NP swabs (Same as for Xpert Xpress) Timing of reference standard: Within 24h of sample collection (on presentation at ED); no further detail Blinded to index test: Not stated; seems unlikely Incorporated index test: Yes
Flow and timing	Time interval between index and reference tests: Same swab [B], or paired collection [A] All patients received same reference standard: Yes, all had all 4 assays Missing data: None reported, no participant flow diagram reported Uninterpretable results: None reported Indeterminate results (index test): [A] no invalid results, [B] 1 'invalid' result; not reported if this was a 'presumptive positive' (E gene only) on Xpert Xpress or no result Indeterminate results (reference standard): None reported Unit of analysis: Unclear; text refers to 'patients' so presumed patient‐based
Comparative
Notes	Funding: No funding statement reported Publication status: Pre‐print Source: bioRxiv Author COI: No COI statement provided
Methodological quality
Item	Authors' judgement	Risk of bias	Applicability concerns
DOMAIN 1: Patient Selection
Was a consecutive or random sample of patients enrolled?	Unclear
Was a case‐control design avoided?	Yes
Did the study avoid inappropriate exclusions?	Unclear
Did the study avoid inappropriate inclusions?	Yes
Could the selection of patients have introduced bias?		Unclear risk
Are there concerns that the included patients and setting do not match the review question?			Low concern
DOMAIN 2: Index Test (Antigen tests)
DOMAIN 2: Index Test (Rapid molecular tests)
Were the index test results interpreted without knowledge of the results of the reference standard?	Unclear
If a threshold was used, was it pre‐specified?	Yes
Could the conduct or interpretation of the index test have introduced bias?		Unclear risk
Are there concerns that the index test, its conduct, or interpretation differ from the review question?			Unclear
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?	No
Reference standard does not incorporate result of index test?	No
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?	No
Were all patients included in the analysis?	Unclear
Did all participants receive a reference standard?	Yes
Were results presented per patient?	Yes
Could the patient flow have introduced bias?		High risk