Standard E2 test vs. Sensitive E2 test

[RickB]

Never had much difference between sensitive and standard E2. That difference varies on the individual's particular health situation (interference). Use the standard unless you have known inflammatory issues or be diligent and run both. At the end of the day most people aren't running replicates at a particular lab so machine and operator precision is a black box.

Any ideas on why they'd use different ranges for standard and sensitive?

Whether sensitive is truly more accurate or not, why would they use a different range than standard, when both tests are supposedly telling us the same damn thing - our estradiol.

 

[tareload]

Any ideas on why they'd use different ranges for standard and sensitive?

Whether sensitive is truly more accurate or not, why would they use a different range than standard, when both tests are supposedly telling us the same damn thing - our estradiol.

Here's an old post that should help:

Are These Side Effects from HCG and/or Anastrozole?

Hi, great question. I’ve listened to the lectures and I understand how this comment can be frustrating: It’s going to be extremely difficult for someone not trained in the field to try to make sense of this. This issue is further clouded by the fact that no distinction between RIA and LC/MS...

forums.t-nation.com

Since TNation now has these posts as Member's only I will reproduce the post for those who don't have access.

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Hi, great question. I’ve listened to the lectures and I understand how this comment can be frustrating:

Good study’s provided by hardartery , but my question was … can you show me anything that proves what your video is claiming ?? “Men in their early 20s have e2 levels of 75-100”

It’s going to be extremely difficult for someone not trained in the field to try to make sense of this. This issue is further clouded by the fact that no distinction between RIA and LC/MS estradiol methods is being made.


Let’s go to a definitive study of over 3,000 “normal” men age 40 and over:


Comparison of serum testosterone and estradiol measurements in 3174 European men using platform immunoassay and mass spectrometry; relevance for the diagnostics in aging men.




Go straight to the 99%+tile for testosterone and E2 (Fig. 1 of paper). You can see men top out at 35 nmol/l (T) and 150 pmol/l (E2). Converting this to more commonly used units (on this forum) we get about 1010 ng/dl (Test) and 40.9 pg/ml (E2). That’s a ratio of about 25, which is a function of aromatization (obesity, etc). Compare these values against Arup’s (reference laboratory) upper range:

Estradiol (Adult Males, Children, Postmenopausal Females, or Individuals on Estrogen-Suppressing Hormone Therapy) | ARUP Laboratories Test Directory

Use this mass spectrometry test to measure a wide range of estradiol concentrations. Most useful when low estradiol concentrations are expected, regardless of the patient’s sex assigned at birth. Use to monitor estradiol in individuals on estrogen-suppressing hormone therapies (eg, aromatase...

ltd.aruplab.com

Also compare the T/E2(LCMS) ratio computed above to the average ratio in Table 1:





Look at these parity plots (as they are typically called). Below, you can see the RIA method for testosterone matches well against LC/MS method. Each point is an individual. E2 immunoassay (non-sensitive) is typically (majority of folks) but not always higher than the LC-MS (sensitive) E2 test. Some of these guys are below the parity line on the plots below.




Ok, let’s take an example of some freak 20 year old walking around with total testosterone level of 1500 ng/dl and assume his aromatization rate is normal (T/ LCMS E2 ratio of 25). Using LC/MS E2 assay he would measure about 60.7 pg/ml (1500/1010*40.9). Now let’s say he gets E2 tested using typical RIA method instead of LC/MS method. Using correlation in second panel of Fig. 3 above we get:


E2 (RIA method) = 4.28 + 1.19*60.7 = 76.5 pg/ml estradiol


So are “most” 20-25 year olds walking around with estradiol levels of 75-100? Well we need to qualify which estradiol test we are talking about and the units. Using gold standard LC/MS method accurate for men, the answer is NO. But in the example calculation above I do demonstrate it’s possible using RIA method. For young men with reasonably high T levels and also higher aromatization ratios, it’s also possible but would seem an exception rather than the rule.


The Devil is in the Details so you can’t throw out numbers unless you qualify the units AND the method when it comes to estradiol.


EDIT: a rather long-winded post to demonstrate the answer to the question. Going straight to Arup’s website (link above), the VAST majority of males over 18 are walking around with actual estradiol levels between 10-42 pg/ml (LC/MS method).

 

[tareload]

Any ideas on why they'd use different ranges for standard and sensitive?

Whether sensitive is truly more accurate or not, why would they use a different range than standard, when both tests are supposedly telling us the same damn thing - our estradiol.

I've posted so much about this I've forgotten where they all are. Here's another one:

Experiences of using two methods to measure estradiol in men: E2 (CLIA) Vs E2 (Sensitive)

I have never seen a debate on this. Everyone always says get the e2 sensitive.... I’m interested in how big a difference the two tests truly make. Like what’s the variance?

www.excelmale.com

Two ECLIA instruments may be measuring the same samples but give different results. At the end of the day the ranges you quoted above are close enough to the CDC accepted bias in the methods where they would be deemed "close enough".

Parity close between LCMS E2 (deemed the accepted value shown in the x-axis) and 5 different E2 immunoassays. They aren't all created equal.