Table 1.
Distribution of CT abnormality scores recorded by three readers.
| Standard dose |
Low dose |
||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 5 | 4 | 3 | 2 | 1 | 5 | 4 | 3 | 2 | 1 | ||
| Lung | Emphysema | 320 | 11 | 3 | 0 | 551 | 274 | 26 | 1 | 7 | 577 |
| Ground-glass opacity | 347 | 34 | 4 | 10 | 490 | 309 | 44 | 17 | 17 | 498 | |
| Reticular opacity | 378 | 30 | 11 | 4 | 462 | 342 | 24 | 11 | 0 | 508 | |
| Micronodules | 245 | 18 | 2 | 0 | 620 | 193 | 14 | 0 | 1 | 677 | |
| Bronchiectasis | 276 | 18 | 2 | 4 | 584 | 238 | 19 | 3 | 3 | 622 | |
| Nodules (>5 mm) | 183 | 0 | 2 | 0 | 700 | 185 | 0 | 0 | 1 | 699 | |
| Mediastinum and pleura | Aortic aneurysm | 5 | 1 | 1 | 1 | 169 | 8 | 3 | 0 | 1 | 165 |
| Coronary artery calcification | 131 | 6 | 0 | 1 | 39 | 123 | 8 | 0 | 3 | 43 | |
| Pericardial effusion | 13 | 4 | 0 | 1 | 159 | 11 | 3 | 0 | 1 | 162 | |
| Pleural effusion | 32 | 0 | 0 | 0 | 145 | 28 | 1 | 0 | 0 | 148 | |
| Non-calcified pleural thickening | 117 | 5 | 0 | 0 | 55 | 92 | 9 | 0 | 0 | 76 | |
| Calcified pleural thickening | 14 | 0 | 0 | 0 | 163 | 13 | 1 | 2 | 0 | 161 | |
| Mediastinal tumor | 1 | 1 | 0 | 0 | 175 | 1 | 1 | 0 | 0 | 175 | |
| Lymph node enlargement | 174 | 2 | 0 | 0 | 1 | 165 | 7 | 1 | 0 | 4 | |
The sums of the numbers by three readers are shown in this table. The numbers for the lung abnormalities appearing in this table are the total of numbers at five image levels.