Being a doctor doesn’t make a person a good doctor.
Being a physiologist doesn’t make a person a good physiologist.
Doing a study doesn’t make it a good study.
IAAF helped with a “study” of free testosterone -vs- performance level in athletes at the 2011 & 2013 World Championships. Relating it to the Caster Semenya issue.
Free testosterone may or may not be depressed in athletes that are in an overtrained state. Measuring it without measuring cortisol, baseline testosterone, other overtrained state issues, other testosterone impacting issues makes your data worthless in this context of matching testosterone with performance level.

The use of observational data to set policy in this context is highly unwise.

And on a similar line, cause and effect is cause and effect. Correlation is -not- cause and effect. We don’t live in the 1970’s. Its 2018. We know something about the underlying mechanisms of human performance. We know something about the function of testosterone in human cells. The brain, nervous system, and immune system are the end all and be all of human performance in track & field. Those are -not- about testosterone.
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“Testosterone prohormones such as androstenedione, androstenediol, and dehydroepiandrosterone (DHEA) have been heavily marketed as testosterone-enhancing and muscle-building nutritional supplements for the past decade.”

“Contrary to marketing claims, research to date indicates that the use of prohormone nutritional supplements (DHEA, androstenedione, androstenediol, and other steroid hormone supplements) does not produce either anabolic or ergogenic effects in men. Moreover, the use of prohormone nutritional supplements may raise the risk for negative health consequences.”

G.A.Brown, et al
Testosterone Prohormone Supplements.
Medicine & Science in Sports & Exercise…..Volume 38 #8….August 2006…..pg 1367-1537
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“Testosterone plays a crucial role in neuronal function, but elevated concentrations can have deleterious effects. Here we show that supraphysiological levels of testosterone initiate the apoptotic cascade…….Elevated testosterone concentrations increase cell death……These effects of testosterone on neurons will have long term effects on brain function.”

M. Estradal, et al
Elevated Testosterone Induces Apoptosis in Neuronal Cells
Journal Of Biological Chemistry…..Volume 281…September 1, 2006…page 25492 – 25501
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“The evidence that supraphysiological doses of anabolic androgenic steroids cause neurotrophic unbalance……anabolic androgenic steroids abuse in humans may affect mechanisms that lie at the core of neuronal plasticity.”

S.Pieretti, et al
Brain Nerve Growth Factor Unbalance Induced by Anabolic Androgenic Steroids in Rat
Medicine & Science In Sports & Exercise……Volume 45 #1….January 2013…page 29 – 35
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Drug use & drug testing are a sham and a scam.
Put data ahead of dogma.
Follow the data not the crowd.