Thyroid nodule risk stratification allows clinicians to standardize the evaluation of thyroid cancer risk according to ultrasound features.
To evaluate inter-rater agreement among clinicians assessing thyroid nodules ultrasound features and thyroid cancer risk categories.
Design, setting, and participants
We surveyed Endocrine Society and Latin American Thyroid Society members to assess their interpretation of composition, echogenicity, shape, margins, and presence of echogenic foci of ten thyroid nodule cases. The risk category for thyroid cancer was calculated following the ACR-TIRADS framework from individual responses.
Main outcomes and measures
We used descriptive statistics and Gwet’s agreement coefficient (AC1) to assess the primary outcome of inter-rater agreement for ACR-TIRADS risk category. As secondary outomes the inter-rater agreement for individual features and subgroup analysis of inter-rater agreement for ACR-TIRADS category was performed (ultrasound reporting system, type of practice, and number of monthly appraisals).
A total of 144 participants were included, mostly endocrinologists (82%). There was moderate level of agreement for the absence of echogenic foci (AC1 0.53, 95% confidence interval (CI) 0.24-0.81) and composition (AC1 0.54, 95%CI 0.36-0.71). The agreement for margins (AC1 0.24, 95% CI 0.15-0.33), echogenicity (AC1 0.34, 95% CI 0.22-0.46), and shape assessment (AC1 0.42, 95% CI 0.13-0.70) was lower. The overall agreement for ACR-TIRADS assessment was AC1 0.29, 95% CI 0.13-0.45. The AC1 of ACR-TIRADS among subgroups was similar.
This study found high variation of judgments about ACR-TIRADS risk category and individual features, which poses a potential challenge for the widescale implementation of thyroid nodule risk stratification.