Diagnostic accuracy of CO-RADS in patients with suspected Coronavirus Disease-2019: A single center experience

COVID-19 Reporting and Data System (CO-RADS) is a tool for standardizing the reports of patients with suspected or confirmed Sars-CoV-2 infection. We performed a study of the performance of the CO-RADS in a triage scenario of patients in Brazil.

Data from 426 Computed Tomography (CT) scans from March 2020 through December 2020 were assessed in an ambidirectional, both retrospective and prospective, for the assessment in one of the six categories of the CO-RADS. We assessed sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (PLR), negative likelihood ratio (NLR) Youden's index, Positive and Negative Clinical Utility Index (UC + and UC- respectively) and diagnostic odds ratio (DOR). We also plotted Receiver Operating Characteristics (ROC) curve with Area Under the Curve (AUC) for CO-RADS of >4 (4 + 5).

For CO-RADS classification > 4 (4 + 5) considered positive, the AUC obtained was of 0.89 (95% CI of 0.02), sensitivity of 78% (95% CI of 0.3), specificity of 91% (95% CI of 0.3), PPV of 0.92 (95% CI of 0.02), NPV of 0.41 (95% CI of 0.03), PLR of 0.85 (95% CI of 0.2), and NLR of 0.23 (95% CI of 0.02).

CO-RADS demonstrated overall good diagnostic performance in stratifying patients with suspected Sars-CoV-2 infection, even those without confirmed laboratorial diagnosis, therefore being useful in a triage scenario with lack of resources.