Free Thyroxine Index
Thyroxine Index, Free
FREE THYROXINE INDEX
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Thyroid function test, for the diagnosis of hypothyroidism or hyperthyroidism in conjunction with T4 result.
22 - 37% Uptake
* Reference ranges may change over time. Please refer to the original patient report when evaluating results.
Collect specimen in a red top or SST tube. Test should be ordered in conjunction with a total T4.
Collect specimen in a red top or SST tube. Centrifuge, aliquot serum into a plastic vial and refrigerate. Test should be ordered in conjunction with a total T4.