Is TIRADS a practical and accurate system for use in daily clinical practice?

Abstract

To assess the positive predictive value (PPV) and inter.observer agreement of Thyroid Imaging Reporting and Data System (TIRADS) as described by Kwak et al. Materials and Methods: This was a prospective study wherein ultrasound was performed by two radiologists on patients with thyroid nodules > 1 cm. The third radiologist interpreted archived images. Ultrasound features and TIRADS category were compared with cytology and surgical histopathology. PPV was calculated for all readers combined assessment. Inter.observer agreement was calculated using linear weighted kappa. Results: A total of 238 patients with 272 nodules of mean size 2.9 ± 1.7 cm were included. PPV for malignancy was 6.6%, 32%, 36%, 64%, 59%, and 91% for TIRADS 2, 3, 4a, 4b, 4c, and 5 categories, respectively. Inter.observer agreement was substantial [kappa (k) = 0.61.0.80] for assessment of nodule echogenicity, margins, calcification, and shape and good (k = 0.570, P < 0.001) for assessment of composition of the thyroid nodules. Overall agreement between observers was substantial for assigning TIRADS category [multi.rater weighted kappa coefficient (wt k) = 0.721, P < 0.001]. Conclusions: TIRADS is a simple and practical method of assessing thyroid nodules with high PPV and good inter.observer agreement.