Utility, Limitations, and Pitfalls in Measuring Testosterone: An Endocrine Society Position Statement

Laboratory proficiency testing should be based on the ability to measure accurately and precisely samples containing known concentrations of testosterone, not only on agreement with others using the same method. When such standardization is in place, normative values for total and free testosterone should be established for both genders and children, taking into account the many variables that influence serum testosterone concentration.