The TIRADS classification refers to the Thyroid Imaging Reporting and Data System (2009), or TI-RADS, an ultrasound classification that evaluates specific characteristics of thyroid nodules (shape, borders, vascularization, presence of microcalcifications, and echogenicity) to categorize them. Each category is associated with a specific risk of malignancy and a corresponding intervention. It is a reporting and classification system developed by the American Thyroid Associatio