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Evaluation of the RSNA and CORADS classifications for COVID-19 on chest computed tomography in the Brazilian
Eduardo Kaiser Ururahy Nunes Fonseca1, Bruna Melo Coelho Loureiro1, Daniel Giunchetti Strabelli1
1Hospital das Clinicas HCFMUSP, Faculdade de Medicina, Universidade de Sao Paulo, Sao Paulo, SP, BR.
Insights
The Radiological Society of North America (RSNA) and COVID-19 Reporting and Data System (CORADS) classifications for COVID-19 show strong agreement among experienced radiologists. Both systems correlate well, aiding in accurate chest CT interpretation for coronavirus disease.
Area of Science:
- Radiology
- Infectious Diseases
- Medical Imaging
Background:
- Accurate interpretation of chest computed tomography (CT) findings is crucial for diagnosing coronavirus disease (COVID-19).
- Standardized reporting systems, such as the COVID-19 Reporting and Data System (CORADS) and the Radiological Society of North America (RSNA) classification, aim to improve consistency in CT interpretation.
- Evaluating the agreement and correlation between these systems in diverse populations is essential for their clinical utility.
Purpose of the Study:
- To determine the correlation between the CORADS and RSNA tomographic classifications for COVID-19 in the Brazilian population.
- To assess the inter- and intra-observer agreement for both classifications among radiologists with varying experience levels.
Main Methods:
- Chest CT images from 100 RT-PCR-positive COVID-19 patients were independently classified using CORADS and RSNA criteria by radiologists with different experience levels.
- Inter- and intra-observer concordance for each classification were calculated using kappa statistics.
- Concordance between the CORADS and RSNA classifications was assessed.
Main Results:
- The RSNA classification demonstrated almost perfect inter-observer agreement (kappa=0.892) among similarly experienced reviewers.
- CORADS showed substantial agreement (kappa=0.642) among similarly experienced reviewers.
- A significant correlation was found between RSNA and CORADS classifications (Kendall coefficient=0.899), with substantial intra-observer agreement for both.
Conclusions:
- Both RSNA and CORADS classifications exhibit excellent inter-observer agreement among experienced radiologists, though agreement decreases with less experienced reviewers.
- A strong correlation exists between the two classification systems.
- Combined analysis with RT-PCR results did not identify any false-negative cases for COVID-19 detection using these CT classifications.
Objective:
To determine the correlation between the two tomographic classifications for coronavirus disease (COVID-19), COVID-19 Reporting and Data System (CORADS) and Radiological Society of North America Expert Consensus Statement on Reporting Chest Computed Tomography (CT) Findings Related to COVID-19 (RSNA), in the Brazilian population and to assess the agreement between reviewers with different experience levels.
Methods:
Chest CT images of patients with reverse transcriptase-polymerase chain reaction (RT-PCR)-positive COVID-19 were categorized according to the CORADS and RSNA classifications by radiologists with different levels of experience and who were initially unaware of the RT-PCR results. The inter- and intra-observer concordances for each of the classifications were calculated, as were the concordances between classifications.
Results:
A total of 100 patients were included in this study. The RSNA classification showed an almost perfect inter-observer agreement between reviewers with similar experience levels, with a kappa coefficient of 0.892 (95% confidence interval [CI], 0.788-0.995). CORADS showed substantial agreement among reviewers with similar experience levels, with a kappa coefficient of 0.642 (95% CI, 0.491-0.793). There was inter-observer variation when comparing less experienced reviewers with more experienced reviewers, with the highest kappa coefficient of 0.396 (95% CI, 0.255-0.588). There was a significant correlation between both classifications, with a Kendall coefficient of 0.899 (p<0.001) and substantial intra-observer agreement for both classifications.
Conclusion:
The RSNA and CORADS classifications showed excellent inter-observer agreement for reviewers with the same level of experience, although the agreement between less experience reviewers and the reviewer with the most experience was only reasonable. Combined analysis of both classifications with the first RT-PCR results did not reveal any false-negative results for detecting COVID-19 in patients.
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