Ordinal scale used in this study based on the British Society of Thoracic Imaging (BSTI) reporting template10
| Ordinal scale for study | BSTI grade | Features on X-ray |
| 0 | CVCX3-Non-COVID-19 | Alternative pathology such as CVCX3—Non-COVID-19 pneumothorax with no features of COVID-19 identified |
| 1 | CVCX0—Normal | No pathology seen |
| 2 | CVCX2—Indeterminate for COVD-19 or atypical features | Poor quality film or central/basal consolidation |
| 3 | CVCX1—Classic findings of COVID-19 | Peripheral ground glass opacities |