Cunarro‐Lopez 2020.

Study characteristics
Patient Sampling	Purpose: diagnosis of SARS‐CoV‐2 infection (mild COVID‐19 disease); to examine maternal‐perinatal outcomes in pregnant women with suspected COVID‐19 according to the result of a RT‐PCR test and to investigate possible variables that could be useful for predicting a negative RT‐PCR result Design: cross‐sectional cohort study, retrospective data collection Recruitment: obstetrics patient (pregnant, in labour or puerperium) with suspected COVID‐19 who attended the hospital Sample size: n = 111 (68 cases) Inclusion criteria: all obstetrics patients (pregnant, in labour or puerperium) with suspected COVID‐19 who attended the hospital Exclusion criteria: non‐conclusive RT‐PCR result, those patients who did not undergo obstetric follow‐up in the hospital and asymptomatic patients with SARS‐CoV‐2 infections
Patient characteristics and setting	Facility cases: RT‐PCR positive for SARS‐CoV‐2 Facility controls: RT‐PCR negative for SARS‐CoV‐2 Country: Spain Dates: 10 March 2020‐12 May 2020 Symptoms and severity cases: mild 52%, moderate 28%, severe 12%, critical 6% controls: mild 79%, moderate 16%, severe 5%, critical 0% Demographics: mean age cases 34 years, controls 32 years M%/F%: cases 0.0/100.0, controls 40.0/100.0 Exposure history: not specified
Index tests	Fever Cough Shortness of breath Diarrhoea Body temperature Breathing frequency
Target condition and reference standard(s)	TC: SARS‐CoV‐2 infection RS: RT‐PCR for SARS‐CoV‐2 (nasal or pharyngeal swab)
Flow and timing	Timing of RS not specified
Comparative
Notes	Funding: by University of Alcalá (COVID‐19 UAH 2019/00003/016/001/023) and by (FIS‐PI18/00912) the Instituto de Salud Carlos III (Plan Estatal de I + D+I 2013‐2016) and co financed by the European Development Regional Fund
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?	No
Did the study avoid inappropriate inclusions?	Yes
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?			High
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?		Unclear risk