Sensitive vs Non-sensitive T, E2

[TallandSmall]

I recently did sensitive and non-sensitive tests through labcorp in the same draw. I know this isn't anything new, but I was surprised at the size of the difference, so here's my anecdote. TRT dose at trough.

E2, LC/MS - 33.2
E2, ECLIA - 50.4 (+52%)

Total T, LC/MS - 672.4
Total T, ECLIA - 859 (+28%)

Free T, Equilibrium - 23.33
Free T, Direct - 19.6 (-16%)

 

[readalot]

Free T, Equilibrium - 23.33
Free T, Direct - 19.6 (-16%)

Very cool data set! Not surprised knowing you.

Also notice the units for these two...

Equilibrium dialysis is ng/dl

"Direct"/RIA is pg/ml.

Hence the "Direct" FT result comes back at ~2 ng/dl. Clearly nonsensical. So the direct FT is only correlated with FT and doesnt measure FT.

23.3/1.96 = 11.88

Factor of 12x difference.

The typical rule of thumb is 7x so your data points are even more extreme.

Well done!!

 

[TallandSmall]

Also notice the units for these two…

I hadn’t. I just assumed they’d be consistent in their reporting units. I’ll stick with the sensitive tests, but I was curious in case you needed a faster turn around for suspected estrogen issues, but 52% is a pretty big difference and could lead to different dose or AI decisions. I wouldn’t be crazy about 50 on TRT but I think 33 is ok for now.

 

[Tbaz192]

Damn.

Seeing that difference in E2 testing is NOT awesome. I’m so tired of waiting 14 days for sensitive E2. Especially im on cycle or trying to dial in my e2 for a change in dose on Test or whatever.
So I definitely can’t rely on normal e2 tests, especially if it’s a compound that can effect that versus not effecting ultra sensitive.

The unfortunate side of being highly sensitive to estrogen changes. Dumb.

 

[Liter O' Test]

Damn.

Seeing that difference in E2 testing is NOT awesome. I’m so tired of waiting 14 days for sensitive E2. Especially im on cycle or trying to dial in my e2 for a change in dose on Test or whatever.
So I definitely can’t rely on normal e2 tests, especially if it’s a compound that can effect that versus not effecting ultra sensitive.

The unfortunate side of being highly sensitive to estrogen changes. Dumb.

been waiting since fucking august for my quest result
chatgpt told me labcorp is faster but more expensive

 

[Photon]

been waiting since fucking august for my quest result
chatgpt told me labcorp is faster but more expensive

Priced bout the same

Post in thread 'Basic/Affordable/Comprehensive Bloodwork'

Sep 4, 2025

Updated, thanks to @BamaCrazy for providing the missing prices

• Photon

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[Photon]

I recently did sensitive and non-sensitive tests through labcorp in the same draw. I know this isn't anything new, but I was surprised at the size of the difference, so here's my anecdote. TRT dose at trough.

E2, LC/MS - 33.2
E2, ECLIA - 50.4 (+52%)

Total T, LC/MS - 672.4
Total T, ECLIA - 859 (+28%)

Free T, Equilibrium - 23.33
Free T, Direct - 19.6 (-16%)

Id reckon if you pull both e2s for awhile, you'll get a rough sense of how it correlates and can roughly estimate your sensitive e2 based off normal e2. Might be a way to get by the long testing times..

 

[readalot]

Id reckon if you pull both e2s for awhile, you'll get a rough sense of how it correlates and can roughly estimate your sensitive e2 based off normal e2. Might be a way to get by the long testing times..

All the literature data is there. Fun to compare. If you use other shit that can interfere with eclia then LCMS seems like a no brainer. There is no standardized E2 assay through CDC Host program with Quest.

Hormones Certified Assays and Participants

List of Hormone Certified Assays

www.cdc.gov

 

[Tbaz192]

been waiting since fucking august for my quest result
chatgpt told me labcorp is faster but more expensive

What in the world. Get a refund for it

 

[Duke309]

All the literature data is there. Fun to compare. If you use other shit that can interfere with eclia then LCMS seems like a no brainer. There is no standardized E2 assay through CDC Host program with Quest.

Hormones Certified Assays and Participants

List of Hormone Certified Assays

www.cdc.gov

The cross reaction with other steroids makes ECLIA completely worthless to correlate unless you stick to test only. Can get crazy high E2 results on ECLIA while on tren for example.

 

[readalot]

The cross reaction with other steroids makes ECLIA completely worthless to correlate unless you stick to test only. Can get crazy high E2 results on ECLIA while on tren for example.

Imagine going in and asking at Quest what eclia instrument they are running ATM. "Ma'am, I really need to know I am running tren currently."