Which tests have been requested?: Hi All, Well... - Thyroid UK

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Which tests have been requested?


Hi All,

Well the 2nd dr I’ve seen I n the surgery has agreed to do more tests but I’m not sure what 1 of them is.

%THYR - what is this?

This test request states %THYR, Thyroid antibodies

Other test request for Thyroid Function and Vitamin D

Comments say borderline TSH, tired (I wish that was all my symptoms!)

Background info: from medichecks (All on previous posts)

TSH is 5.07 mIU/L 0.27 - 4.2

Thyroglobulin antibodies 194 IU/mL 0 - 115

Thyroid peroxidase antibodies 66.2 IU/mL 0 - 34

She’s told me to take 1 x ferrous Fumarate 210mg 2 x daily for my deficient ferritin - nhs test 10 ug/L 12 - 250, is this dose sufficient?

Sorry for repeating things from earlier posts, mainly want to know what the %THYR IS.

I’m fasting to have bloods done in the morning.

Thanks x

3 Replies

I am in the United States but I believe this may be the test that your physician is referring to.

Free thyroxine (FTI or FT4). Free thyroxine (T4) can be measured directly (FT4) or calculated as the free thyroxine index (FTI). The FTI tells how much free T4 is present compared to bound T4. The FTI can help tell if abnormal amounts of T4 are present because of abnormal amounts of thyroxine-binding globulin.

helvellaAdministrator in reply to Shecallsitabuggy

Free T4 index (Free Thyroxine Index or FTI) is, I believe, not now performed in the UK.

Free thyroxine index

The Free Thyroxine Index (FTI or T7) is obtained by multiplying the total T4 with T3 uptake.[2] FTI is considered to be a more reliable indicator of thyroid status in the presence of abnormalities in plasma protein binding.[2] This test is rarely used now that reliable free thyroxine and free triiodothyronine assays are routinely available.


I wish they’d get rid of it here. I hate that test because the numbers are not always accurate and it makes things harder to interpret. And for some reason the emphasis is on T4, which has to be converted to T3. Its a ridiculous test. I was just hoping I could figure out what %THYR could actually be.

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