TSH tests: which is correct?

[Chrys]

Having had a private TSH test done by Medichecks (+FT3, FT4) and one by the NHS from the same clinic blood draw, the TSH results came back:

Medichecks 2.0

NHS 1.59.

Huh?????

[SeasideSusie Remembering]

Chrys

Were the reference ranges the same?

Did you do the tests at the same time of day, after an overnight fast and drinking water only before the test?

[Chrys in reply to SeasideSusie]

As in the OP, same blood draw, and yes and yes.

[silverfox7]

It’s highly possible the labs they were tested in use different ranges so without that info we have t a clue!

[Pixielula]

That happened to my daughter she did her own blood draw at 2am put half into nhs half into blue horizon. NHS 6.8 THS blue horizon over 10. Luckily she managed to get treatment on the nhs for thyroid replacement ref ranges were the same!!!!!

[StitchFairy in reply to Pixielula]

Wow that's a huge difference! Seems to add even more weight to the argument that TSH isn't the be all and end all that docs tell us it is, and they should go by the FT4 and FT3 numbers instead.

[Chrys]

Cancel my previous comments. The blood test was done in our local surgery on 1st October in anticipation of a Haemo apptmnt yesterday. 3 separate blood draws were done, one for Haemo, one for TSH, and one for Medichecks. At the Haemo apptmnt, I asked and received a printout of the results form, from which I quoted above the TSH as 1.59µU/mL, however on closer reading of the printout, while the Haemo results were dated 1st October, the TSH is dated 30th July, indicating that the NHS has not done a new TSH test as requested, and the consultant just printed out the last result they had.

Why am I not surprised? This is not the first time our local Phlebotomy lab has c****d up results.

[Chrys in reply to Chrys]

I am now in posession of the NHS THS result, taken from the same blood draw as Medichecks, whose result was 2.0mlU/L

NHS result 1.63µU/mL or 1.63U/mL, different units used on two separate printouts.

The test was done fasting and >24hr from levo.

I am still surprised at the variation, and although it is not huge, and given that as TSH is the only result GP's prescribe from, such a variation, if around the range limits, would affect this.