Charpentier 2020 [A].

Study characteristics
Patient Sampling	Purpose: Diagnosis of current acute‐phase infection and current convalescent‐phase infection Design: Multi‐group study to estimate sensitivity and specificity [1] Confirmed COVID patients (88 samples from 54 patients) [2] Pre‐pandemic non‐COVID‐samples (120 samples) [2a] Samples for testing as part of routine clinical care (n = 56) [2b] Serum samples corresponding to a cross‐reactivity panel (n = 64) Recruitment: [1]‐[3] Samples collected in the Virology Laboratory of Bichat‐Claude Bernard and Saint‐Louis University‐Hospitals both in Paris, France Prospective or retrospective: [1] and [3] unclear [2] retrospective Sample size: 262 (88) samples of which 208 (88) were eligible for our review Further detail: [1] Patients with a confirmed COVID‐19 diagnosis by a positive nasopharyngeal sample RT‐PCR [2] Collected before November 2019
Patient characteristics and setting	Setting: Hospital inpatients (40/54) and outpatients (14/54) (mixed) Location: Virology Laboratory of Bichat‐Claude Bernard and Saint‐Louis University‐Hospitals both in Paris, France. Country: France Dates: Not stated Symptoms and severity: 54 patients: 29 hospitalised in intensive care, 11 hospitalised in infectious diseases, so 74% with severe infections 14 outpatients Demographics: Median age was 52 years (range: 27–80), 36 were males. Exposure history: Not stated Non‐Covid group 1: [2] Pre‐pandemic Source: Virology Laboratory of Bichat‐Claude Bernard and Saint‐Louis University‐Hospitals both in Paris, France. All collected before November 2019 [2a] Samples for testing as part of routine clinical care (n = 56) [2b] Serum samples corresponding to a cross‐reactivity panel (n = 64): Coronaviruses (HKU1, NL63, 229E and OC43; n = 20), malarial (n = 26), respiratory viruses (influenza A [n = 2], influenza B [n = 1], respiratory syncytial virus [n = 2], metapneumovirus [n = 1], rhinovirus [n = 1]), sera with acute CMV infection (n = 2), acute EBV infection (n = 1), HIV‐HBV co‐infection (n = 1), acute parvovirus B19 infection (n = 1), toxoplasma (n = 1). Samples containing auto‐antibodies (4 rheumatoid factor and 1 systemic lupus erythematosus) Non‐Covid group 2: Suspected COVID‐19, negative or no RT‐PCR (not included in review) Source: Virology Laboratory of Bichat‐Claude Bernard and Saint‐Louis University‐Hospitals both in Paris, France. Time not stated Characteristics: 54 healthcare workers who presented with clinical symptoms during the epidemic period for whom SARS‐CoV‐2 RT‐PCR was negative or not carried out
Index tests	Test name: [A] Covid‐Presto® test rapid Covid‐19 IgG/IgM [B] NG‐Test® IgM‐IgG COVID‐19 [C] Abbott SARS‐CoV‐2 IgG kit Manufacturer: [A] AAZ, Boulogne‐Billancourt, France [B] NG Biotech, Guipry, France [C] Abbott, IL, USA Antibody: [A] IgG and IgM [B] IgG and IgM [C] IgG Antigen target: [A]‐[C] Not stated Evaluation setting: [A] and [B] POC test used in lab [C] Lab test used in lab Test method: [A] and [B] Lateral flow test [C] Chemiluminescent microparticle immunoassay Timing of samples: [A] 88 samples between day 4 and day 42 after onset of symptoms. 4‐9 days pso: 18/88 10‐14 days pso: 33/88 15‐42 days pso: 37/88 [B] Subgroup of 59 samples among the 88 samples between days 7 and 28 after onset of symptoms 7‐9 days pso: 6/59 10‐14 days pso: 22/59 15‐28 days pso: 31/59 [C] 57 samples: 7‐9 days pso: 6/57 10‐14 days pso: 22/57 >14 days pso: 29/57 Samples used: [A]‐[C] Serum Test operator: [A]‐[C] Lab personnel Definition of test positivity: [A] and [B] According to manufacturer’s instructions; results were read and interpreted 10 min after depositing serum. [C] The assay cut‐off is an index of 1.40 and the assigned grey zone is comprised between 1.12 and 1.68. Blinding reported: Not stated Threshold predefined: [A] and [B] yes, visual‐based [C] yes, according to manufacturer's instructions
Target condition and reference standard(s)	Reference standard: [1] RT‐PCR, threshold not stated Samples used: Nasopharyngeal samples Timing of reference standard: Not stated Blinded to index test: Yes, prior Incorporated index test: No Definition of non‐COVID cases: [2] Pre‐pandemic samples (before November 2019) [3] RT‐PCR or no reference standard Samples used: [2] Pre‐pandemic samples (before November 2019) [3] Not stated or no reference standard Timing of reference standard: [2] and [3] Not stated Blinded to index test: [2] and [3] yes, prior Incorporated index test: No
Flow and timing	Time interval between index and reference tests: Not stated All patients received same reference standard: no Missing data: yes (sensitivity for [B] in 59/88 samples; sensitivity of for [C] in 57/88 samples; specificity for [B] and [C] in 52/120 samples) Uninterpretable results: Not stated Indeterminate results: yes [one sample was positive in the grey zone with Abbott SARS‐CoV‐2 IgG assay (index: 1.45)] Unit of analysis: Samples
Comparative
Notes	Funding: Not stated Publication status: Published paper Source: Journal of Clinical Virology Author COI: Not stated
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?	No
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?			High
DOMAIN 2: Index Test (All tests)
DOMAIN 2: Index Test (Antibody tests)
Were the index test results interpreted without knowledge of the results of the reference standard?	Unclear
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?	Yes
The reference standard does not incorporate the index test	Yes
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?			High
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?	No
Were all patients included in the analysis?	Yes
Did all participants receive a reference standard?	No
Were results presented per patient?	No
Could the patient flow have introduced bias?		High risk