Free test measurement units/format?

[imperator]

Got this value on free test a few months ago, I've seen free test displayed in various formats in multiple places on the internet but never understood what's the most common way to observe it. Also, feel free to give me your thoughts on the value itself. Is it of any significance without additional tests along with it? Thanks, appreciate it.

 

[shartking]

That's the most basic of all Google searches. It's like asking someone to convert inches to centimeters.

 

[imperator]

That's the most basic of all Google searches. It's like asking someone to convert inches to centimeters.

Alright, please explain this to me. How does this graph make any sense considering it's also pg/ml as mine and the reference ranges have literally nothing to do with one another? I'm not retarded I'm asking for a reason. I could've worded it better, maybe. Now we got the graph, I'm still trying to understand what the difference is.

 

[kosp]

Seems like a good level. Don't worry about it. And Total?

 

[Jin23]

Got this value on free test a few months ago, I've seen free test displayed in various formats in multiple places on the internet but never understood what's the most common way to observe it. Also, feel free to give me your thoughts on the value itself. Is it of any significance without additional tests along with it? Thanks, appreciate it.


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Unfortunately free T levels are still a bit of an undetermined territory. This is reflected in the varying results and the reference values of different labs. Specifically, it reflects different techniques of determining free T: equilibrium dialysis, ultrafiltration, direct immunoassay, or maybe if it's calculated and not directly measured then it depends which method of calculation was used.

In short, you can not compare/convert between labs. Just use the labs reference range to judge where you are at or use a calc, but one that acknowledges the allosteric binding of shbg which is not linear.

 

[imperator]

Seems like a good level. Don't worry about it. And Total?

At that time I was just trying out that lab so I only got free T and some random shit tested, but I'll get a more comprehensive one soon since everything went great and quick there. I'll probably create a log thread as well or something.

Unfortunately free T levels are still a bit of an undetermined territory. This is reflected in the varying results and the reference values of different labs. Specifically, it reflects different techniques of determining free T: equilibrium dialysis, ultrafiltration, direct immunoassay, or maybe if it's calculated and not directly measured then it depends which method of calculation was used.

In short, you can not compare/convert between labs. Just use the labs reference range to judge where you are at or use a calc, but one that acknowledges the allosteric binding of shbg which is not linear.

As always, very insightful. This type of elaborate and straightforward answer cannot be found randomly online. Thank you, this basically clears up the confusion.

 

[buck]

I don't really care what format it is reported in. The value is always judged within the range it is given. It is not a hard number. Even in the same measurement system different labs and machines can come up with a different value using the same format. As machines can be calibrated differently etc.

 

[imperator]

I don't really care what format it is reported in. The value is always judged within the range it is given. It is not a hard number. Even in the same measurement system different labs and machines can come up with a different value using the same format. As machines can be calibrated differently etc.

Yeah, I was basically just a bit stunned to see so many different measurements across the internet, with the same units (so we're not talking about conversions necessarily here even though it's also a bit annoying to see so many units displayed, but that's fine can just be converted). Jin's answer explained it pretty well and I'm glad to see your thought too, thanks for the reply!

 

[readalot]

See parts I and II starting here for the blow by blow...

Calculate Free Testosterone with TruT by FPT

The idea of SHBG as a sponge that sucks up large amounts of testosterone and leaves your free T low doesn't seem to be how it really works. The way I understand it, high SHBG makes your meager production (revealed by the free T) look like it's normal or even high when it isn't. The SHBG is...

www.excelmale.com

You had the direct imminoassay which is typically off by a factor of 7 from equilibrium dialysis or calculated FT via Vermeulen.

Also here:

Public Service Announcement: "Piss Poor" Direct RIA fT measurement (HELP is on the way)

Hey Folks, thought I would update the graph for free T reference ranges based on LC-MS/MS+ED and compare with Labcorp's direct RIA fT reference range. What the hell do you do with with your direct fT measurement if you want to compare with equibrium dialysis reference ranges? Take the Labcorp...

www.excelmale.com

 

[readalot]

And I will throw this in here as well for those who want more on calculated FT methods =f(TT, SHBG, HSA)...cFTv vs TruT. Vermeulen still kicking ass.

Reference Intervals for Free Testosterone in Adult Men Measured Using a Standardized Equilibrium Dialysis Procedure

Again you heard it here first only at Nelson's ExcelMale! @Nelson Vergel Was going to drop this bomb a few days ago but you let down the curtains early LOL! https://onlinelibrary.wiley.com/doi/abs/10.1111/andr.13310 Reference Intervals for Free Testosterone in Adult Men Measured Using a...

www.excelmale.com