84436 Assay of total thyroxine
Also known as: total T4, serum thyroxine, T4 level
Quantitative assay of total serum thyroxine (T4) concentration, measuring bound and free thyroid hormone.
In Plain Language
thyroid hormone test
Clinical Context
Screen for thyroid function; abnormal with hyperthyroidism/hypothyroidism; interpretation requires free T4 or TSH.
RVU Information
CPT 84436 does not have a physician work RVU assigned by CMS. Reimbursement for this code is determined by payer-specific fee schedules.
Billing & Documentation
Lab and pathology codes require an order from the treating provider with clinical indication. For molecular pathology and genetic testing, document the specific analytes tested and clinical rationale.
How This Code Compares
This code has a work RVU of 0.00, meaning it does not have a physician work component assigned by CMS. In the Pathology & Lab category, 94% of codes share this characteristic.
Specialties
Frequently Asked Questions
What is CPT code 84436?
CPT 84436 (Assay of total thyroxine) is a Pathology & Lab code. Quantitative assay of total serum thyroxine (T4) concentration, measuring bound and free thyroid hormone.
Who uses CPT code 84436?
CPT 84436 is used by Clinical Chemistry, Endocrinology, Pathology. Screen for thyroid function; abnormal with hyperthyroidism/hypothyroidism; interpretation requires free T4 or TSH.
When is CPT 84436 used?
Screen for thyroid function; abnormal with hyperthyroidism/hypothyroidism; interpretation requires free T4 or TSH.
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CPT® is a registered trademark of the American Medical Association. Data sourced from CMS Physician Fee Schedule RVU26A. Descriptions, synonyms, and clinical context are original content by RVU Edge.