4 Wks After PCT, Free Test Levels vs Total

[humza8b]

I just got my labs done, after 4 weeks of pct with Nolva

My total testosterone is 661.9 ng/dL ( ref range is 260-1000 )
Free test is shown as 27.79 pg/mL ( ref range is 15-50)

So If I convert my free test from pg/mL to ng/dL, I have only 2.77 free test out of 661?
Still wondering if 2.77 is a possibility ? and its not in RED color on my report/its in normal range, so just wondering

[mnben87]

Is this LabCorp units? IIRC, they don’t have the correct units on FT (should be in ng/dL as well IIRC).

[ncsugrad2002]

Just look at where you fall inside the range, IMO. There’s debate on whether it’s actually a typo on the unit or a result of the method of measurement Labcorp is using, but, regardless, the range is designed around the test method, so they should align.

[swoops39]

@humza8b

Free test is shown as 27.79 pg/mL

Labcorp uses the wrong units. Should be ng/dL. Your value looks great

[humza8b]

Thank you for the reply everyone, it isn’t labcorp , just a local lab in my region.
I believe it should be ng/dL.
The Methodology written in the report is : Chemiluminescence Immunoassay Technique

Also I am being told that Free test levels are about 2% of Total Test levels, so (661x2% = 13), I have 2 times of 13x2 ≈ 27? if it makes any sense ?

[swoops39]

@humza8b

if it makes any sense

Don’t suppose they checked your SHBG?

[readalot]

If you want the gory details…there’s no “debate” here. There’s exactly 0% chance that Labcorp would continue to result out incorrect units on an FDA approved blood test if that was actually an issue.

In your particular case, you’ve had a variant “direct” RIA free Test measurement which typically varies by a factor of most typically 5 to 7 (the test variant is measuring a proxy for free Test and highly correlates with free Test, but the slope is not 1) vs a calibrated free Test calc or gold standard ED/LCMS free Test measurement.

The story that the units of the direct free testosterone assay (RIA) are reported incorrectly is myth.

Realistic TRT Recomp Progress

As you probably know, the “direct” RIA free T is trash and only a windsock for what the true free T level is. But alot of doctors are comfortable with it since it gives them an indication of where a guy is (not on an absolute scale, but on a relative scale, relative to the true scale). A lot of guys (rightfully so) are completely confused by this as the RIA test correlates with free T but actually isn’t measuring free T. It will read only a fraction of the gold-standard dialysis free T test a…

Realistic TRT Recomp Progress

Thanks for bringing this up. Many try to rationalize this and I completely understand why. I understand why you say that but the units aren’t screwed up. Those are the actual units. Example report: [image] Guys decided to shift the scale by 10 to try and make sense of the results. You can go over to Excel male and see the endless walls of text me and another guy spent on that. Labcorp would not screw up the units on the test. As you dig into the bowels of the organization, you have …

Realistic TRT Recomp Progress

[image] [image] In recent years, the RIA method has been criticized by some experts as inaccurate due to substantial numerical discrepancies between RIA and EqD results, and too heavily influenced by either TT [7] or by SHBG [8]. The numerical differences lead to confusion in interpreting clinical results and can complicate efforts to establish biochemical standards for the diagnosis of TD. Based on these issues, some experts advocate that the RIA method should not be used in clinical …

Benefits of Estrogen for TRT Patients

Because the slope of the direct EIA test data when plotted against the equilibrium dialysis or calculated free T numbers is much less than 1. It’s hard to read high on the direct free T method unless you really push on your free T. Correlation of various methods for measuring free T. Simple linear regression models with 95% prediction intervals. A, Equilibrium dialysis vs. mass action with SHBG by IRMA (y 0.02 1.20x; r 0.99; P 0.0001). B, Equilibrium dialysis vs. direct RIA (y 0.52 2.50x; r 0…

Benefits of Estrogen for TRT Patients

Here I’ll answer your question and help @vonko1988 at the same time. vonko just shared his total T is about 500 ng/dl and his SHBG is 43 nmol/L. Let’s punch in the numbers assuming his albumin is 4.3 g/dL: [image] Calculated free T is 8.9 ng/dL (1.8% free). This number has been shown in literature to be pretty accurate with equilbrium dialysis number (good correlation but some dispute on accuracy, I won’t belabor that here). Ok let’s compare this calculated free T to his EIA (direct) num…

Rough math… 13 / 2.77 = 4.8 ~ 5 ( all units in ng/dL).

If you have your SHBG, we can confirm your 2% free Test assumption.

** For the interested reader, take a look at the links above. It’s important that incorrect information doesn’t keep getting repeated so we can increase understanding and literacy in this field.**

[ncsugrad2002]

@readalot

The story that the units of the direct free testosterone assay (RIA) are reported incorrectly is myth

That’s what I thought. I couldn’t remember if it was “off” by a factory of 5 or 7, guess it was more like 5. I’ll have to save your post this time for the next time this comes up.

[swoops39]

@readalot

reported incorrectly is myth

No kidding … so it’s not really suppose to be ng/dL for Labcorp? It’s just off by a factor of 5?

[mnben87]

@swoops39

It’s just off by a factor of 5?

Really important to have the reference ranges in this case.

[aaronca]

Just out of curiosity, how many weeks after stopping Nolva did you do these labs?

[humza8b]

just the next day of exact 4 weeks, 40/40/20/20 I wanted to do it for 6 weeks, but Injected 100mg test prop as soon as I got replies on my post.
& no I didn’t have my SHBG tested.

[aaronca]

Your test levels won’t be accurate that soon. Just an example , I had labs done several weeks after coming off Nolvadex, my TT was 794 (250 higher than my pre cycle labs). But after a couple of months I retested and they bounced back to pre lab numbers of 550.

I wouldn’t put too much weight or thought into the current numbers, personally.