December 12, 2011
False Positive

Ok, I’m going to explain this one more time:

There is no danger of a “false positive” in testosterone testing. This discussion is specific to Ryan Braun, but it’s also the case in all modern sports testing. I thought I’d detailed this enough in my recent SI piece, but I guess it’s worth making even more clear. 

The initial testing done is a simple ratio. Anything over 4:1 of testosterone to epitestosterone triggers the second, more accurate and precise test. The ratio test isn’t very accurate, which is why it is no longer used as a standalone. It used to be, until the secondary test (gas chromatography and isotope ratio) became widely available. But having a high ratio proves NOTHING; it simply triggers the more accurate test.

So why do the ratio test at all? The GC-IRMS test is expensive and time consuming. You (and the lab techs in Montreal) don’t want to do hundreds of them. The ratio test is simply a way to spend time and resources on the cases that need that kind of time and attention. 

So to summarize: T/E ratio is pretty accurate, but not to be relied on. Good enough to use as a trigger. Second test? Very, very, very accurate. False positives, like masking agents, remain one of the red herrings of drug testing.

  1. toobadyouresobeautiful reblogged this from willcarroll
  2. stardog reblogged this from willcarroll
  3. jcsnotes reblogged this from willcarroll
  4. willcarroll posted this