FT3/rT3 ratio = 0.2 Not sure what this means - Thyroid UK

Thyroid UK

141,243 members166,489 posts

FT3/rT3 ratio = 0.2 Not sure what this means

AmandaK profile image
6 Replies

Further to my post yesterday, I now have the ratio. According to STTM it should be over 20!

Given that maths isn't my strong point, perhaps my calculations should be checked: 

FT3: 4.17 pmol/L

rT3: 18 ug/ L

So, the actual rT3 result is above 14 and this, according to STTM, is excessive.

The  ratio is 0.2 and should be over 20.

The result fits with a low normal FT4 reading of 15.59 (12-22).

These results are one of many I posted yesterday - please see healthunlocked.com/thyroidu...

for further info.

I would really appreciate help with this as it does look as though I finally have some clues as to what may be going on - and that there may be an underlying cause to all my symptoms.

With thanks,

Amandak

Written by
AmandaK profile image
AmandaK
To view profiles and participate in discussions please or .
Read more about...
6 Replies
ann_g_k profile image
ann_g_k

Many thanks - I actually used the STTM calculator (see stopthethyroidmadness.com/r... and made sure I entered the correct units of measurement for each (they are different measurement units). Please feel free to double check I've entered them correctly - brain not in gear today!

Clutter profile image
Clutter in reply toann_g_k

Ann_g_k,

I'd contact STTM for help.  There may be problems with the calculator or the conversion calculator they supply.

ann_g_k profile image
ann_g_k in reply toClutter

Thank you Clutter. In fact we had the same idea so I'm waiting a reply from them. I'll let you know what they say.

humanbean profile image
humanbean

There is a problem with the STTM calculator. It's surprising how many people using UK units get an answer of 0.2!

Use these instructions to calculate it instead :

tpauk.com/main/article/how-...

humanbean profile image
humanbean in reply tohumanbean

I get the following result :

(4.17 x 100)/18 = 23 (to the nearest whole number)

What are the reference ranges on your results?

For STTM to pick a particular number (14) and saying anything over that is excessive, is nonsensical without specifying the units to be used and the reference range they are comparing to.

Edit : STTM do this a lot - mention a number without units or reference ranges. It is annoying and potentially dangerous.

ann_g_k profile image
ann_g_k in reply tohumanbean

Many thanks Humanbean, that makes a huge difference! The ref range is 10-24 so 18 is within range.

I had hoped that the ratio results would answer a few questions, but no - back to the drawing board for me then.

I don't know if you saw the full Blue Horizon results (see the link above). Marz wonders if central hypothyroidism may be the problem, though I have my doubts. I'd be interested in your feedback.

With appreciation,

Amandak (aka ann_g_k)

Not what you're looking for?

You may also like...

RT3/FT3 Ratio

Dears, I just used STTM to calculate my reverse T3 Ratio. My RT3 is (0.62 ug/L) and the normal...
Fahad888 profile image

RT3:fT3 ratio help

My brain is failing me. I just got my rT3 results back from Genova, coming in at 0.31 nmol/L. I...
hose1975 profile image

Rt3 ratio 14

Hi I posted my full bloods a couple of days ago and only clutter responded saying they all looked...
sulamaye profile image

Have RT3 and FT3 result. Need help!

Possibly one for the admins here. I've reposted as I got confused over my readings and then have...
BexyLS profile image

Confused by Medichecks reverse T3 ratio calculation

As the NHS will not do the rT3 test and my endo suggested it should be done, I have these recent...
amasufindme profile image

Moderation team

See all
PurpleNails profile image
PurpleNailsAdministrator
SlowDragon profile image
SlowDragonAdministrator
Jaydee1507 profile image
Jaydee1507Administrator

Content on HealthUnlocked does not replace the relationship between you and doctors or other healthcare professionals nor the advice you receive from them.

Never delay seeking advice or dialling emergency services because of something that you have read on HealthUnlocked.