Techniques to measure testosterone in the elderly.

In today's clinical and research settings, there is an unfortunate lack of consistency for the term "measuring testosterone status." This term is often used to refer to a measure of biologic androgen activity rather than the specific measurement of the chemical concentration of the testosterone steroid molecule. Even the measurements of chemical concentrations show considerable methodologic differences. This is true for measurements in elderly men, as well as in other populations, including women. All of the current methods for measuring total testosterone have limitations, especially with regard to low concentrations. In addition, unresolved questions concerning the active form of the hormone preclude definitive determination of which form of testosterone and which other androgen hormones are best suited for measuring androgen activity. When measurement techniques are compared, the numbers correlate with each other but certainly do not represent the same value. There is a need for a consensus as to which forms of hormones should be measured to best assess androgen status, and there is a need to standardize the procedures used to measure these hormones.