Bhattacharya 2021.

Study characteristics
Patient Sampling	Purpose: diagnosis of SARS‐CoV‐2 infection (mild COVID‐19 disease); to evaluate the clinical symptoms among patients with suspected COVID‐19 presenting to screening outpatient clinics to develop and validate a clinical symptom‐based scoring system Design: cross‐sectional cohort study, prospective data collection Recruitment: patients presenting to an outpatient clinic at a tertiary care hospital Sample size: n = 378 (125) Inclusion criteria: patients who were suspected of having COVID‐19 and tested, provided informed consent and were contacted successfully by phone, from 1066 suspected patients who were tested during this period, 384 patients were enrolled in the study based on the availability of informed consent and successful telephonic communication). Suspicion was based on the testing advisory developed by the Indian Council of Medical Research (ICMR), Version 5, dated 18 May 2020. "ILI symptoms", defined as acute respiratory infection with fever ≥ 38 °C AND cough. Exclusion criteria: no PCR test result
Patient characteristics and setting	Facility cases: positive SARS‐CoV‐2 test Facility controls: negative SARS‐CoV‐2 test Country: India Dates: 17 June 2020‐1 July 2020 Symptoms and severity: not specified, mostly mild to moderate severity Demographics: mean age overall 35.6 years M%/F% overall: 65.1/34.9 Exposure history: not specified
Index tests	Body temperature (cutoff fever >37.8°C) Sore throat Cough Headache Myalgia Breathlessness Nausea Vomiting Diarrhoea Loss of smell
Target condition and reference standard(s)	TC: SARS‐CoV‐2 infection RS: RT‐PCR for SARS‐CoV‐2 (nasal + throat swab)
Flow and timing	Index tests and RS both at presentation, phone interview after test was taken but before result was generated
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?	No
Was a case‐control design avoided?	Yes
Did the study avoid inappropriate exclusions?	Unclear
Did the study avoid inappropriate inclusions?	No
Could the selection of patients have introduced bias?		High 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?		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?	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?	No
Could the patient flow have introduced bias?		Unclear risk