RIA Vs ELISA: Which Lab Assay To Trust?

[TheBeard]

I'm off everything, hormonal or supplemental.

My free T came back at 26 pg/ml (2.9-28) with ELISA lab testing method. It's usually been hovering around that value for the past years I have tested it with this method.

A few weeks later I switched labs and went to one that tests free T with RIA, and free T came back at 13 pg/ml (8-41). That's with no change in diet, supps or lifestyle at all between the two tests.

Besides the absolute value big difference, I am at the lower end of one and the upper end of the other.

Which one speaks the truth?

@haidut @olive @RisingSun

 

[RisingSun]

I can tell you two things:

- lab ranges correspond to the extreme values observed for the specific population measured by that lab over a given period of time.

- if you want an accurate value of free testosterone, have it measured with LC-MS/MS

 

[yerrag]

Where's the OP?

 

[TheBeard]

Where's the OP?

I used to be in Asia and the latest lab with low values was performed in France