Category: THYROID | Code: K4306
Free T4-Index (FTI)
Function
This test assesses FT4 levels by measuring total T4 and thyroid hormone-binding index. This examination is useful in assisting the diagnosis of thyroid disease.
| Test Schedule | Estimated Test Result | Container | Substance | Stability |
|---|---|---|---|---|
| Monday - Wednesday < 11 am | 2 days | Plain | Serum, 1 mL | 7 days, 2-8⁰C |
Condition
Not lysate and not lipemic
Method
Electrochemiluminescence Immunoassay
Score Reference
THYROXINE BINDING CAPACITY, units: Thyroxine Binding Index: (TBI) 0-19 years: 0.8-1.2 TBI > or =20 years: 0.8-1.3 TBI T4 TOTAL (T4): 0-5 days: 5.0-18.5 mcg/dL 6 days-2 months: 5.4-17.0 mcg/dL 3-11 months: 5.7-16.0 mcg/dL 1-5 years: 6.0-14.7 mcg/dL 6-10 years: 6.0-13.8 mcg/dL 11-19 years: 5.9-13.2 mcg/dL > or =20 years: 4.5-11.7 mcg/dL FREE THYROXINE INDEX: 0-5 days: 5.1-20.8 mcg/dL 6 days-2 months: 5.5-18.0 mcg/dL 3-11 months: 5.7-16.8 mcg/dL 1-5 years: 5.9-15.0 mcg/dL 6-10 years: 6.0-13.9 mcg/dL 11-19 years: 5.9-13.2 mcg/dL > or =20 years: 4.8-12.7 mcg/dL