Study characteristics
Patient Sampling  Purpose: analyse the clinical features and imaging manifestations of COVID‐19Design: cross‐sectional, single‐centre, retrospective studyRecruitment: clinically suspected cases who were sent to hospital for screeningSample size: n = 86 (n = 11)Inclusion criteria: clinically suspected patientsExclusion criteria: not specified
Patient characteristics and setting  Facility cases: positive RT‐PCR via nasopharyngeal swabFacility controls: negative RT‐PCR via nasopharyngeal swab (1x)Country: ChinaDates: 23 January 2020‐16 February 2020Symptoms and severity: fever, cough, dyspnoea, sore throat, fatigue, systemic soreness, runny noseDemographics: M/F: total 39/47, cases: 5/6, controls 34/40Case group: mean age 40.73 ± 11.32 years, 5 men. Control group: mean age 39.67 ± 13.90 years, 34 menExposure history: 7/11 COVID‐19 patients (63.6%) had a history of travel to Hubei (5 Wuhan, 1 Huanggang, 1 Xiaogan), 2 patients had close contact with the COVID‐19 patients, and 2 taxi drivers
Index tests  Fever
Cough
Dyspnoea
Sore throat
Fatigue
Systemic soreness
Runny nose
Target condition and reference standard(s)  TC: SARS‐Cov‐2 infection
RS: RT‐PCR (nasopharyngeal swab)
Flow and timing  Time interval not specified
Comparative   
Notes   
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?  Unclear      
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?  No      
Could the conduct or interpretation of the index test have introduced bias?     High 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?  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?     Low risk