UK Lung Sceeen (UKLS) nodule categories
| Solid | Non-solid or part solid | |
| Category 1 | Nodules containing fat or with a benign pattern of calcification are considered benign. Nodules <15 mm3 or if pleural or juxta pleural ≤3 mm | |
| Category 2 | Intraparenchymal nodules with a volume of 15–49 mm3. Pleural or juxtapleural nodules with a maximal diameter of 3.1–4.9 mm. | Nodules with a maximal non-solid component diameter <5 mm. Where there is a solid component, the component volume is <15 mm3 |
| Category 3 | Intraparenchymal nodules with a volume of 50–500 mm3. Pleural or juxtapleural nodules with a maximal diameter of 5–9.9 mm. | Nodules with a maximal non-solid component diameter of >5 mm. Where there is a solid component, the component volume is 15–500 mm3 |
| Category 4 | Intraparenchymal nodules with a volume >500 mm3. Pleural or juxtapleural nodules with a maximal diameter of ≥10 mm. | Nodules with a solid component with a volume >500 mm3 |