Fink 2021.

Study characteristics
Patient Sampling	Purpose: diagnosis of SARS‐CoV‐2 infection (mild COVID‐19 disease) ‐ to define clinical and radiological characteristics of COVID‐19 patients within a cohort with respiratory infections in the emergency department Design: cross‐sectional cohort study, prospective data collection Recruitment: patients who presented at the ED of the University Hospital, LMU Munich with signs of a respiratory infection suspicious for COVID‐19 Sample size: n = 219 (72 cases) Inclusion criteria: patients who presented at ED with signs of a respiratory infection suspicious for COVID‐19 and received radiological imaging (chest radiographs/chest X‐ray and/or CT) as well as RT‐PCR for SARS‐CoV‐2 Exclusion criteria: none specified
Patient characteristics and setting	Facility cases: positive RT‐PCR for SARS‐CoV‐2 Facility controls: negative RT‐PCR for SARS‐CoV‐2 Country: Germany Dates: 16 March 2020‐12 April 2020 Symptoms and severity: mild to moderate to severe. ICU admission: cases 27%, controls 14%. Deaths: cases 5%, controls 3% Demographics: age: controls mean 59.5 years, cases mean 60.0 years M%/F%: cases 68.1/31.9, controls 56.5/43.5 Exposure history: not specified
Index tests	Fever (> 38 °C)
Target condition and reference standard(s)	TC: SARS‐CoV‐2 infection RS: RT‐PCR for SARS‐CoV‐2 (nasopharyngeal and oropharyngeal swab)
Flow and timing	RS and index test both taken at presentation
Comparative
Notes	Funding: open access funding enabled and organised by Projekt DEAL
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?			Unclear
DOMAIN 2: Index Test (All tests)
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?	Unclear
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 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
Could the reference standard, its conduct, or its interpretation have introduced bias?		Low risk
Are there concerns that the target condition as defined by the reference standard does not match the question?			Low concern
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
Could the patient flow have introduced bias?		Low risk