Fingerprick tests reference ranges : Hi I've... - Thyroid UK

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Fingerprick tests reference ranges

Maztee profile image
18 Replies

Hi I've stopped taking biotin so am ready to order a fingerprint test. Try as I might to compare the tests and prices it is beyond my brain capacity to do this and also to find out the reference ranges so that I can compare the results with previous ones that I have. I know that the T4 reference range is always 12 -22 so that would be a start.Does there happen to be a table with the various tests available and their reference ranges? I expect this is too much to ask so if anyone can tell me if their T4 results have the range 12-22 that would be a great help. Thank you very much.

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Maztee profile image
Maztee
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18 Replies
humanbean profile image
humanbean

If you have a test result with a range of 12 - 22 and another test for the same thing but with a range of 7 - 14, you can compare them by looking at the percentage through the range.

Test 1, result = 14, range = 12 - 22 is 20% of the way through the range.

Test 2, result = 8.4, range = 7 - 14 is also 20% through the range and shows that the result is equivalent to test 1.

Test 3, result = 14, range = 7 - 14 is 100% through the range and shows that the result is substantially higher than both test 1 and test 2.

Regarding biotin...

It is only necessary to stop taking biotin for 2 - 7 days before a test. The higher your dose the longer you would need to stop taking it. But once you've stopped and done your testing you can go back on biotin.

Biotin isn't dangerous. Instead, a blood sample with higher than usual levels of biotin in it may affect the way the test machine functions and this can mean that results are inaccurate. But it is the machine which has a problem, not the patient.

Edit : I always stop biotin for a week before testing anything, but that is my personal choice.

Maztee profile image
Maztee in reply tohumanbean

Thanks. Yes I am stopping it for a week. Was going to order test then got confused about ranges and how they'd compare so thanks for how to do the calculations!

humanbean profile image
humanbean in reply toMaztee

To get the calculations done for you :

thyroid.dopiaza.org/

thyroid.chingkerrs.online/

SlowDragon profile image
SlowDragonAdministrator

Only stop biotin 5-7 days before test

Only test early Monday or Tuesday morning

Maztee profile image
Maztee in reply toSlowDragon

Oh no I'll have to take biotin again and do the test next Monday, Tuesday. I just want TSH (not really though) T3, T4 and possibly rT3 if it's of any use and helps to show if there is poor conversion though the advice seems conflicting. There is one that does cortisol and magnesium too which I haven't had done or not for a long time. I don't need antibodies done as I don't have a thyroid and they are consistently non-existent/low for 40+ years including recently.

SlowDragon profile image
SlowDragonAdministrator in reply toMaztee

We don’t recommend testing Reverse T3 …..very expensive test

So cheapest without antibodies is MMH but has to be DIY finger prick test

monitormyhealth.org.uk/full...

10% off code here

thyroiduk.org/getting-a-dia...

or

Medichecks Thyroid plus antibodies and vitamins

medichecks.com/products/adv...

Blue Horizon Thyroid Premium Gold includes antibodies, cortisol and vitamins

bluehorizonbloodtests.co.uk...

Only do private testing early Monday or Tuesday morning.

Link about thyroid blood tests

thyroiduk.org/getting-a-dia...

Tips on how to do DIY finger prick test

healthunlocked.com/thyroidu...

Medichecks and BH also offer private blood draw at clinic near you, or private nurse to your own home…..for an extra fee

Maztee profile image
Maztee in reply toSlowDragon

Thank you. It's so difficult to calculate all of these! It's exhausting trying to work out what to do. I'm going to do this then speak to someone privately (on the list) about the results who can liaise with my gp and if I need t3 I may or may not need to get it privately.After that I need to get PTH and calcium, D3 done to see if it's hyperparathyroidism.

My GP just isn't interested.

helvella profile image
helvellaAdministrator in reply toMaztee

I don't think that    SlowDragon meant that stopping biotin more days ahead is a problem. Rather reassuring that you wouldn't need to stop longer than 5-7 days. (And that is very cautious.)

Maztee profile image
Maztee in reply tohelvella

Yes thank you 🙂

SlowDragon profile image
SlowDragonAdministrator in reply toMaztee

Is your biotin in vitamin B complex?

If yes….just take separate folate and separate B12 up until you do test

Maztee profile image
Maztee in reply toSlowDragon

Yes thanks though that would be more expense though I'll check out prices...😕

Blu-cat11 profile image
Blu-cat11

Hi I did a finger prick test last week. I recommend that you make sure you are warm before the test. A nurse friend suggested warming hands in a bowl of water first. Hope that is helpful.

wavedancers profile image
wavedancers in reply toBlu-cat11

I'd also suggest STANDING with the finger over the tube on a table. I couldn't get my blood out any other way.

Maztee profile image
Maztee in reply toBlu-cat11

Thanks. My daughter will be doing it. She did her own! I have regular eye jabs which are painful so I won't be able to do it (sensitised to pain!) She can get me by surprise but I plan to follow the instructions to warn my blood etc then she can grab it and do it!

SlowDragon profile image
SlowDragonAdministrator in reply toMaztee

Make sure to exercise before hand…..10 mins walking or similar

Bearo profile image
Bearo

I found drinking plenty of water the day before as well as just before was important for me when doing fingerbprick (but if I’m having a GP test at the same time I’ll ask nurse to pop some in the private tube)

Maztee profile image
Maztee in reply toBearo

Good idea. Can they do that?

Bearo profile image
Bearo in reply toMaztee

I’ve asked a few times and haven’t been refused yet. I ask as if I’m expecting them to do it ……”and can you just fill this one so that I can send it off….”.

Once the vial wasn’t the right size or shape for the nurse to fill it easily so she had to fiddle around but she still did it.

They probably think I’ve had it agreed with the doctor beforehand.

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