Pooled analysis of diagnostic performance of the instrument-read Quidel Sofia SARS antigen Fluorescent Immunoassay (FIA)

Giuseppe Lippi; Brandon M Henry; Mario Plebani

Pooled analysis of diagnostic performance of the instrument-read Quidel Sofia SARS antigen Fluorescent Immunoassay (FIA)

EJIFCC. 2023 Jul 10;34(2):123-141. eCollection 2023 Jul.

Authors

Giuseppe Lippi^{1

2}, Brandon M Henry^{1

3}, Mario Plebani^{1

4}

Affiliations

¹ IFCC Task Force on COVID-19, Milano, Italy and IFCC WG on SARS-CoV-2 variants.
² Section of Clinical Biochemistry and School of Medicine, University of Verona, Verona, Italy.
³ Clinical Laboratory, Division of Nephrology and Hypertension, Cincinnati Children's Hospital Medical Center, Cincinnati OH, USA.
⁴ Department of Medicine, University of Padova, Padova, Italy.

PMID: 37455844
PMCID: PMC10349315

Abstract

Background: This article presents a critical literature review and meta-analysis of diagnostic performance of Quidel Sofia SARS antigen Fluorescent Immunoassay (FIA), a rapid diagnostic antigen test (RDT-Ag) adapted for automatic reading with portable instruments, thus potentially combining the advantages of point-of-care testing with those of a laboratory-based immunoassay.

Methods: We conducted an electronic search in PubMed and Scopus with the keywords "Quidel" OR "SOFIA" AND "Antigen" AND "SARS-CoV-2" OR "COVID-19" up to March 24, 2023, for identifying articles containing data on accuracy of Quidel Sofia SARS antigen FIA for diagnosing acute SARS-CoV-2 infections. We selected those where test accuracy was compared to that of a reference SARS-CoV-2 molecular assay, and with sufficient information for constructing a 2×2 table.

Results: A total number of 18 articles (48165 samples; 9.8% positive at molecular testing) were included in this meta-analysis, averaging 24 sample cohorts. The diagnostic accuracy (summary area under the curve), sensitivity and specificity were 0.980, 0.76 and 1.00 in all samples, 0.981, 0.81 and 0.99 in samples collected from symptomatic patients, 0.931, 0.55 and 1.00 in those taken from asymptomatic patients, and 0.960, 0.77 and 0.99 in samples from mixed cohorts of patients, respectively. Minor and clinically negligible differences of accuracy could be found by comparing test results in nasal and nasopharyngeal swabs.

Conclusion: Quidel Sofia SARS Ag FIA meets the minimum performance criteria of accuracy for SARS-CoV-2 antigenic testing, thus combining satisfactory diagnostic performance with the advantages of being potentially used as a portable device.

Keywords: COVID-19; SARS-CoV-2; antigen; diagnosis; immunoassay.

Publication types

Review