Pathology/Lab Coding Alert

Question: Our lab frequently gets denials for thyroid function tests. Why does this happen?


Georgia Subscriber
Answer: Your denials may be caused by several factors. CMS has a National Coverage Determination (NCD) for thyroid testing that outlines the coverage criteria for these procedures.

Your best bet is to consult the NCD and learn the billing requirements for thyroid function tests such as 84443 (Thyroid stimulating hormone [TSH]) or 84479 (Thyroid hormone [T3 or T4] uptake or thyroid binding ratio [THBR]). Some private payers may publish different requirements, so you should also check with other payers that have denied your claims.

Medicare does not cover most screening tests, including screening for thyroid disorders (V77.0, Special screening for endocrine, nutritional, metabolic, and immunity disorders; thyroid disorders). According to the Medicare NCD, "tests for screening purposes that are performed in the absence of signs, symptoms, complaints, or personal history of disease or injury are not covered except as explicitly authorized by statute."
 
The NCD provides an exhaustive list of payable ICD-9 codes, and those not listed, Medicare will deny. Acceptable codes for thyroid testing include malignant neoplasm of thyroid gland (193), premature menopause (256.31), fever (780.6), abnormal weight gain (783.1), throat pain (784.1), and many more. But remember, you should always code based on the information from the ordering physician, not based on what will get you paid.

If the NCD doesn't lead you to the right information, determine whether your patient may have exceeded the frequency limits for these tests. The NCD states that "testing may be covered up to two times a year in clinically stable patients," but Medicare may reimburse more frequent testing based on necessity.