Method Name
Calculation
Aliases
Free Thyroid Index; FTI, FTI
Specimen Required
One Lithium Heparin separator or one SST/gel tube
Specimen Minimum Volume
0.5 mL of blood
Special Instructions
Free Thyroid Index (FTI) is a calculation based on the total T4 and T3-uptake values. FTI estimates Free T4 levels.
Performing Laboratory
As ordered. Turn around time is 4 hours.
Reference Values
1.4-3.1