Veyrenche 2021 [A].

Study characteristics
Patient Sampling	Purpose: Diagnosis of current acute‐phase infection Design: Two‐group study to assess sensitivity and specificity [1] Covid‐19 cases (n = 45) [2] Non‐Covid controls (n = 20) Group [2] not eligible for our review as < 25 samples leaving a single‐group study to estimate sensitivity only Recruitment: [1] Patients admitted in Montpellier University Hospitals between 14 March and 11 April 2020 who tested positive for SARS‐CoV‐2 RNA [2] Samples collected in the pre‐COVID‐19 period (2017‐2018) in patients Prospective or retrospective: [1] Prospective [2] Retrospective Sample size: 65 (45) but 45 (45) included in our study Further detail: [1] Inclusion: Hospital inpatients with RT‐PCR confirmed SARS‐CoV‐2 infection. Any disease severity Exclusion: Not stated [2] Inclusion: Samples from patients collected pre‐pandemic (2017‐2018) Exclusion: Not stated
Patient characteristics and setting	Setting: Hospital inpatients Location: Montpellier University hospitals (Centre Hospitalier Universitaire de Montpellier, Montpellier) Country: France Dates: 14 March to 11 April 2020 Symptoms and severity: 26/45, 58% cases 'severe' according to WHO guideline (similar numbers per Ct subgroup) All hospitalised Demographics: 32/45, 71% male Exposure history: Not stated
Index tests	Test name: [A] SARS‐CoV‐2 IgG immunoassay (Alinity) [B] ELISA COVID‐19 THERA02 IgM assay [C] SureScreen COVID‐19 IgM/IgG Rapid Test [D] Syzbio SARS‐CoV‐2 IgM/IgG Antibody Assay Kit Manufacturer: [A] Abbott Diagnostics, Illinois, USA [B] Theradiag, Marne la Vallee, France [C] SureScreen Diagnostics Ltd, Derby, UK [D]Syzbio Biotech Joint Stock Co., Ltd, Wuhan, China Antibody: [A] IgG [B] IgM [C] IgM and/or IgG [D] IgM and/or IgG Antigen target: [A] N‐protein [B] S‐protein [C] not stated [D] not stated Evaluation setting: [A] [B] Laboratory test [C] [D] POCT performed in lab Test method: [A] CMIA [B] ELISA [C] [D] lateral flow Timing of samples: Day 1‐20 pso. 1‐7 days (n = 22) 7‐14 days (n = 14) 14 ‐ 20 days (n = 9) Samples used: [A] [B] [C] [D] Plasma Test operator: Nicolas Veyrenche, Karine Bolloré and Amandine Pisoni have performed experiments (Pathogenesis and Control of Chronic Infections, INSERM, Etablissement Français du Sang, CHU Montpellier, Université de Montpellier, Montpellier, France). All tests were performed in the laboratory of Virology. Definition of test positivity: [A] ratio (S/C) >= 1.4 is positive, < 1.4 negative. [B] positive cut‐off is ratio >= 1. [C] [D] any signal visible, even weak, at 15 mins on the test line is positive. Blinding reported: Not stated. Threshold predefined: Yes, according to manufacturer
Target condition and reference standard(s)	Reference standard: RT‐PCR; Allplex™ 2019‐nCoV Assay (Seegene, Seoul, South Korea); COVID‐19 confirmed‐subjects were grouped according to the average value of the cycle threshold (Ct), Ct ≤ 25, 25 < Ct < 35 and Ct ≥ 35. Samples used: Nasopharyngeal Timing of reference standard: Hospital admission ranged from 1‐20 days pso; PCR performed prospectively on admission within a few hours after collection Blinded to index test: Yes, prior Incorporated index test: No
Flow and timing	Time interval between index and reference tests: [1] Same day All patients received same reference standard: Yes for [1], group [2] excluded from review Missing data: yes, group [2] excluded from review Uninterpretable results: none reported Indeterminate results: no indeterminate threshold Unit of analysis: patients
Comparative
Notes	Funding: This work was funded by the Montpellier University Hospital, Muse I‐SITE Program Grant, University of Montpellier. Publication status: Published paper Source: Journal of Medical Virology Author COI: The authors declared that there were no conflicts of interest.
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?	Unclear
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?	Yes
Were all patients included in the analysis?	Yes
Did all participants receive a reference standard?	No
Were results presented per patient?	Yes
Could the patient flow have introduced bias?		High risk