Drager 2020.

Study characteristics
Patient Sampling	Purpose: diagnosis of SARS‐CoV‐2 infection (mild COVID‐19 disease); to analyse clinical characteristics of patients with SARS‐CoV‐2 suspicion Design: cross‐sectional cohort study, prospective data collection Recruitment: all symptomatic patients presenting at the Corona outpatient clinic at the Carl Gustav Carus University hospital of Dresden Sample size: n = 2257 (163 cases) Inclusion criteria: all patients presenting themselves at the outpatient clinic: patients with symptoms (not further specified) + high‐risk contacts or returning from a high‐risk area where tested for SARS‐CoV‐2 Exclusion criteria: non specified
Patient characteristics and setting	Facility cases: RT‐PCR‐positive for SARS‐CoV‐2 Facility controls: RT‐PCR‐negative for SARS‐CoV‐2 Country: Germany Dates: 09 March 2020‐31 March 2020 Symptoms and severity: mostly cough and upper airway symptoms, mild to moderate, no hospitalisations specified Demographics: median age overall 39 years overall 45% male 55% female 32% had pre‐existing Illness Exposure history: 5% tested based on epidemiology (returning from high‐risk area), 27% had exposure to COVID‐19‐positive patient(s)
Index tests	Cough Headache Nasal congestion Muscle pains Sore throat Fever Diarrhoea Shortness of breath Vomiting/nausea
Target condition and reference standard(s)	TC: SARS‐CoV‐2 infection RS: not specified (throat swab)
Flow and timing	Timing not specified
Comparative
Notes	Funding: none declared
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 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 (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?	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 3: Reference Standard
Is the reference standards likely to correctly classify the target condition?	Unclear
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?		Unclear risk
Are there concerns that the target condition as defined by the reference standard does not match the question?			Unclear
DOMAIN 4: Flow and Timing
Was there an appropriate interval between index test and reference standard?	Unclear
Did all patients receive the same reference standard?	Yes
Were all patients included in the analysis?	Yes
Could the patient flow have introduced bias?		Unclear risk