Factors and Outcomes of Inappropriate Thyroid Ultrasonography

Area of Science:

• Endocrinology
• Radiology
• Health Services Research

Background:

• Thyroid cancer incidence has significantly increased, largely due to the detection of small papillary thyroid cancers.
• Overutilization of thyroid ultrasonography (TUS) contributes to overdiagnosis, potentially leading to unnecessary patient interventions and harm.

Purpose of the Study:

• To determine the frequency of inappropriate TUS (iTUS) orders.
• To identify factors associated with iTUS.
• To assess clinical outcomes following iTUS.

Main Methods:

• Retrospective cohort study of adult patients undergoing their first TUS between January 2017 and December 2021.
• A natural language processing model classified TUS orders as appropriate or inappropriate based on clinical indications.
• Analysis of patient, clinician, and encounter characteristics associated with iTUS.

Main Results:

• Out of 11,442 TUS orders, 7.6% were classified as inappropriate.
• Factors associated with iTUS included younger age, hyperthyroidism, non-endocrinology referrals, and orders not linked to in-person appointments.
• iTUS was associated with lower rates of thyroid nodule detection, biopsies, thyroidectomies, and cancer diagnoses compared to appropriate TUS.

Conclusions:

• Nearly 1 in 13 TUS orders were inappropriate, indicating significant overuse.
• Targeted strategies are needed to optimize TUS use, particularly for younger patients and those referred by non-endocrinology specialties.
• Mitigating iTUS can help reduce overdiagnosis and overtreatment in thyroid cancer.