Note: The sum of all patients entered in this table is larger than the overall number of patients included in our study, since each patient could fulfill multiple surgical criteria simultaneously.

Abbreviations/definitions: AITD, autoimmune thyroid disease; Atypia, patients with a history of FNA cytology consistent with atypia of undetermined significance or other atypical features; Compression, the presence of long-standing, significant compressive symptoms of the neck, such as dysphagia, vocal cord paralysis, pressure, or neck pain; FN/HCN, patients with FNA cytology consistent with follicular neoplasm/Hurthle cell neoplasm or suspicion for any of the above; Genetic: patients carrying mutations known to cause specific histological types of thyroid cancer, or patients operated for thyroid nodules, in the presence of strong family history of thyroid cancer; Large/growing, patients with thyroid nodules > 4 cm in largest diameter or nodules growing over time; Lymphoma, patients operated with a total thyroidectomy for primary thyroid lymphoma; MNG, multinodular goiter; Other, patients operated in the thyroid for various reasons (e.g., abscess, intrathyroidal parathyroids, cancers metastatic to the thyroid, operation for tracheostomy); Patient selection, patients operated with a total thyroidectomy for nodular disease, not fulfilling other established criteria, who were operated due to their choice; Radiation history, patients with thyroid nodules and history of exposure to ionizing radiation who opted directly for surgery; Thyroglossal duct, patients undergoing total thyroidectomy, for the main reason of the presence of a large thyroglossal duct cyst; Thyroid cancer, any fine needle aspiration cytological report consistent with a specimen positive or suspicious for any type of thyroid cancer.