USC ENDOCRINE SERVICES LABORATORY

Free Triiodothyronine Index (FT3I) 

 

METHODOLOGY

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This is not a test per-se.  It is a calculated ratio of two tests: Total T3 / THBR
 

PERFORMED  

 

Tuesday & Friday

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REPORTED  

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2 days

 

REMARKS

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FT3-Index Components: Triiodothyronine (T3), Thyroid Hormone Binding Ratio (THBR)

 

REFERENCE RANGE

 

80 - 180 (no units)

CPT CODES

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84480 (34), 84479 (THBR)