Quest Diagnostics - Testosterone, Free (Dialysis) and Total, MS

madman · Apr 25, 2024

Just to be clear!

*FT (test code 36170) is calculated by equilibrium dialysis using a modified Vermeulen equation

Quest Diagnostics: Test Directory

testdirectory.questdiagnostics.com

Quest Diagnostics offers the following measurements:

TT (by LC-MS/MS, test code 15983) includes sex-hormone bound globulin (SHBG)-bound T, albumin-bound T, and FT.
FT (test code 36170) is calculated by equilibrium dialysis using a modified Vermeulen equation.2
Bioavailable T (test code 14966) is TT minus SHBG-bound T. Bioavailable T is calculated using the Sodergard equation.3

Nelson Vergel · Apr 25, 2024

Testosterone Testing

Question 1. What is testosterone (T)? T is the prototypical male hormone, though it is also produced in females. T is the most abundant androgen secreted by the male gonads. In females, 25% of T is produced in the ovaries, 25% in the adrenal glands, and 50% in the peripheral conversion of...

www.questdiagnostics.com

Big_Alan · Apr 25, 2024

madman said:
Just to be clear!

*FT (test code 36170) is calculated by equilibrium dialysis using a modified Vermeulen equation

Quest Diagnostics: Test Directory

testdirectory.questdiagnostics.com

Quest Diagnostics offers the following measurements:

TT (by LC-MS/MS, test code 15983) includes sex-hormone bound globulin (SHBG)-bound T, albumin-bound T, and FT.

FT (test code 36170) is calculated by equilibrium dialysis using a modified Vermeulen equation.2

Bioavailable T (test code 14966) is TT minus SHBG-bound T. Bioavailable T is calculated using the Sodergard equation.3

Is the "modified Vermeulen equation" a more accurate method than what you'd get at Labcorp?

madman · Apr 26, 2024

Big_Alan said:
Is the "modified Vermeulen equation" a more accurate method than what you'd get at Labcorp?

If you are speaking in terms of ED assays then no.

When it comes to testing free testosterone you need to use the most accurate assays such as the gold standard Equilibrium Dialysis or Equilibrium Ultrafiltration (next best) especially in cases of altered SHBG if you want to know where your FT level truly sits.

Quest as posted above offers the gold standard Equilibrium Dialysis assay.

You can use the Quest or Labcorp ED assay.

Many tend to go with Quests ED assay as it is cheaper especially through Nelson's discounted labs.

Testosterone, Free (Equilibrium Dialysis) and Total, MS | Discounted Labs

Get an affordable and accurate testosterone test results with our Total Testosterone, M and Free (Equilibrium Dialysis) test. Visit DiscountedLabs.com for more information.

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