Application of the Thyroid Imaging Reporting and Data System in thyroid ultrasonography interpretation by less experienced physicians

PURPOSE: To verify the usefulness of the Thyroid Imaging Reporting and Data System (TI-RADS) for thyroid nodule diagnosis by less experienced physicians. METHODS: From March 2012 to May 2012, ultrasonography-guided fine needle aspiration was performed in 204 thyroid nodules in 195 consecutive patients by four less experienced radiologists (<1 year in thyroid imaging). The number of suspicious ultrasonography features and the total risk score of each thyroid nodule were calculated according to the previous two models suggested by Kwak et al. The Delong method was used to compare the areas under the curve (AUCs) of the two models. Associations between the two models and the risk of malignancy were analyzed using penalized B-splines and the Cochran-Armitage trend test. RESULTS: Among 204 thyroid nodules, 65 were malignant and 139 were benign. The probability of malignancy tended to increase as the number of suspicious ultrasonography features, and the sum of risk scores increased. There was no significant difference in the AUCs of the two models (P=0.673). The Cochran-Armitage trend test demonstrated an increased risk of malignancy as the number of suspicious ultrasonography features and the total risk score increased (P=0.001). CONCLUSION: Both the number of suspicious ultrasonography features and the total risk score are applicable and show comparable results in the risk stratification of thyroid nodules by less experienced radiologists in thyroid imaging.