Quest is, IMPO, the best in the land. BTW, I prefer not to use LabCorp.
Quest assays must be sent to the Nichols Institute. Their "Extraction Method" for Estradiol is the one. They also have a "Free Estradiol" os great interest. And the SHBG tends to be unreliable, so have your Bioavailable Testosterone done there, too, so it will include their good SHBG.
All Quest draw points send these assay samples to Nichols.
To make maters as simple as possible by no more than that,
I think it is the best to go to Quest patients centers and have blood drawn there.
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Funny you have mentioned SHBG.
Mine they did twice. Also twice Albumin.
Once (the right way) with (Testosterone, Free, Bio/Tot)
SHBG - 20 nmol/L ( 23-38 )
Albumin, serum - 4.3 g/dL ( 3.6-5.1 )
Then as separate tests.
SHBG - 24 nmol/L ( 23-38 )
Albumin - 4.6 g/dL ( 3.2-4.6 )
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And they used blood drawn at the same time, so the differences are in the testing method.
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Is there a way to get results electronic way, e-mail letter or preferably excel spreadsheet?
I got mine as mess of a papers trickling down over three weeks with revisions etc,
real mess. Had to retype the mess from 24 pages of paper to get better picture.