Palm Beach, FL

# What is the exact formula for calculating free testosterone based on total testosterone, albumin and sex hormone binding globulin?

1 doctor answer2 doctors weighed in
Geriatrics 32 years experience
Several available: Check out http://www.Issam.Ch/freetesto.Htm for a free testosterone calculator available online. Check out http://www.Eje-online.Org/content/152/3/471.Full for study regarding accuracy of several other calculators.
Created for people with ongoing healthcare needs but benefits everyone.
Dr. Alvin Lin commented
Geriatrics 32 years experience
"But what is the formula used on line? Can I calculate it myself?" Click on 1st hyperlink above, then "Explanation and examples" hyperlink to find formula.
Oct 1, 2012

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Pathology 46 years experience
THanks for the follow-up and for your kind words. Best wishes.
Nov 1, 2016
Pathology 51 years experience
Agree with Dr. Friedlander. The only thing I would add is that K/L ratio is a useless test.
Nov 2, 2016