observation variation in ultrasonography assessment of thyroid nodules

Objective(s): accurate detection and competent management of thyroid nodules, as a common disease, basically depends on the reliability of the ultrasonography (us) report. in this research, we evaluated inter and intra-observer variation among ultrasonography reporters, based on acr-tirads.methods: in this retrospective study, 345 thyroid us images of 150 patients were reviewed. three clinicians with at least 6-year experience in thyroid us reviewed the images twice at 6-8 weeks’ intervals. composition, echogenicity, shape, margin, and echogenic foci based on acr-tirads were reported, independently. inter and intra-observer variations were calculated based on cohen’s kappa statistics.results: 345 ultrasonography images of 150 patients with thyroid nodules (83 women and 67 men) with a mean age of 65 years were reviewed. moderate to the substantial intra-observer agreement was achieved with the highest kapa value in the category of shape (k=0.61-0.77). for tirads level, the moderate intra-observer agreement was observed (k=0.42-0.46). inter-observer agreement for the us category of thyroid nodules was obtained slightly to moderate. composition (k=0.42 and 0.51) and echogenicity (k=0.45 and 0.46) showed the highest overall agreement and margin showed the lowest overall agreement (k=0.18 and 0.19). in assessing tirads level of nodules, a fair agreement was obtained (k=0.23 and 0.29) .conclusion: moderate to substantial intra-observer agreement and slight to moderate inter-observer variation for evaluation of thyroid nodules; shows the need for a computer-aided diagnosis system based on artificial intelligence to assist our physicians in differentiating thyroid nodule characteristics based on explicit image features. an additional training course based on acr-tirads for physicians can be another useful recommendation.