Risk of malignancy in each category based on different TIRADS using CAD and radiologist-based diagnosisa
| TIRADS Classification | Category 1 | Category 2 | Category 3 | Category 4 | Category 5 | P Value |
|---|---|---|---|---|---|---|
| CAD-based on K-TIRADS | 0 (0/0) | 4.8 (1/21) | 12.1 (17/141) | 20.9 (23/110) | 69.2 (126/182) | <.001 |
| Radiologist on K-TIRADS | 0 (0/0) | 0 (0/2) | 6.0 (14/232) | 37.5 (33/88) | 90.9 (120/132) | <.001 |
| CAD-based on ATA-TIRADS | 7.1 (1/14) | 11.4 (9/79) | 10.6 (7/66) | 25.5 (12/47) | 65.7 (134/204) | <.001 |
| Radiologist on ATA-TIRADS | 0 (0/0) | 7.3 (9/124) | 5.5 (6/110) | 26.3 (15/57) | 90.6 (125/138) | <.001 |
↵a The numbers are percentages unless otherwise specified ; 9.6% (44 of 454) of nodules did not meet the criteria for any pattern using the ATA guidelines (isoechoic nodules with suspicious US features) and were classified as “not specified” by the CAD system, while the malignancy risk was calculated to be 9.1% (4 of 44).