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Am i right in my findings?

Look what i just found for the ft4 range now what looks slightly odd to me is that the ranges" 0.7–2.0 ng/dL nanograms per deciliter (ng/dL) or 10–26 picomoles per liter (pmol/L)" this is what i copied, although the ranges here is 0.7-2.0 ng/dl, on my paperwork it has that but stating pmol/l , now am i maybe right in thinking the "pmol/l is for the range 10-26 pmol/l not the other range that is stated on my paperwork?

Sorry if this message dont make sense, im hoping you get what im on about lol.

Now if im right because mine was measured in pmol/l which it states on my blood work in front of me now then the range they done for the measurement is 10-26, with me at 11.0 that puts me just within range, they have put 11.0 pmol/l and range being 7.9-20.0pmol/l the thing is it states that the measurements for pmol/l is from 10-26 on a website i just found and for the ranges to be 7.9-20.0 its measured in ng/dl, am i on to something?

Am i right in my findings anyone? x

sorry if this dont make sense. and sorry for yet another post of me! x

13 Replies

I think you are right that your number of 11 is in a reference range of 10 - 26 pmol/L.

Have a look at the Wiki page here:


This shows several "typical" ranges for FT4 0 and in terms of numbers they make sense with what you have posted.

(Much better to ask with a question than worry and fret and not ask.)



They have put my ft4 result as 11.0 pmol/L with the ranges 7.9-20.0pmol/L is this wrong have they used the wrong measurement cause as I can see pmol/L ref ranges are a easy 10-26 depending on lab results, am I right? X


Sorry - you've got me confused.

Are you saying that on a website, somewhere, you say a range 10 - 26. But on the lab report it says the range is 7.9 - 20?

Ignore what you see on another website - that is simply an example. You MUST use the reference range of the lab that did the test.

Are you able to photograph or scan the report, upload it somewhere, and post a link to it?

Apologies if my answer is no help.



I know I'm very confusing, what I mean is if my lab has used the range 7.9-20.0pmol/l isn't the pmol/l ranges usually in the line of 10-26 and usually the ranges from 7.9 used as measurement of ng/l? X


The reference ranges for FT4 vary HUGELY.

The bottom end could be anywhere from 6 to 12 pmol/L.

The top end could be anywhere from 11 to 26 pmol/L.

Some ranges are much narrower than others - that is, the difference between top and bottom varies hugely.

Forget EVERYTHING about other ranges from websites or previous results. The only range that matters is the one they used for these results.

A typical range expressed in ng/dL might be 0.7 to 1.5 - much different from 7.9 - 20.

Is that what you wanted? Have I confused further? :-)



serum t4 level 11.0 pmol/l

note change to provisional range as 18/01/12

new provisional range 7.9-20.0 pmol/l

1st trimester low limit 6.7 pmol/l

2nd trimester low limit 5.8 pmol/l

3rd trimester low limit 6.1 pmol/l

My ft4 lab result, when I looked up the ref ranges for everywhere the pmol/l was in ranges on 10 so for it to be on my lab report 7.9 surely that is ng/l measurements?


A quick search has found:





All perfectly valid and possible reference ranges!


Thanks, what's that measure in? X


All in pmol/L.


I always refer to the National Academy of Clinical Biochemistry Guidelines. aacc.org/SiteCollectionDocu...

TSH - 0.5-->3.0 mIU/l

FT4 - 9.0-->23.0 pmol/l

FT3 - 3.5-->7.7 pmol/l

Keep in mind that it is your FT3 which is the active hormone and should be roughly a third of your FT4

I rely on the NACB figures because they are consistent and inter-related. The figures used by the UK are a joke. The upper UK FT4 ~ FT3 normal range figures do not reflect an FT4:FT3 ratio of 3

To be frank I am fed up with the UK medical profession and its purported Normal Ranges: There is no such thing. We are individuals with individual FT4 Set-Points (Working Points) and individual TSH & FT3 requirements too.


Thanks, my ft3 was 5.0 my ft4 was 11.0 and my tsh was 1.73 x


Must say, I have no idea why you go there.

That document is over ten years old and is marked as ARCHIVE which usually means that it has been superseded and should no longer be used - being available simply for historic reference.


Ok thanks x


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