Duckstrap zeros in on good arguments

Landis is charged with two anti-doping violations, a IRMS CIR positive for exogenous testosterone, and a GC/MS measured violation of a 4.0 limit for T/E ratio.

At DPF, Duckstrap has come up with theories that explain why both conclusions by the LNDD would be incorrect. These theories make sense even to those who are not swayed by the arguments made in the slide set.

[Edited since the original posting for clarification based on comments by Duckstrap.]
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The IRMS CIR
One of the two charges against Landis is that he had "synthetic" (exogenous) testosterone in his system. This is determined by a test known as the IRMS CIR, which is done on some number of testosterone metabolites. The LNDD found Landis exceeded the allowed ratio on two of four metabolites tested, and declared it a positive test. The WADA standard for the test is vague about how many should be over the limit. Landis has claimed all four should be positive, and others have argued that one or two are sufficient.

At DPF, Duckstrap presents a reasonable case that three or four metabolites should be positive to declare a positive result on the IRMS CIR, based on statistical analysis of published research and other WADA standards.

Duckstrap has reconstructed the "control" data sets from the published studies used to validate the IRMS CIR tests. These are the ones of non-doped samples. He concludes the false positive rate using two metabolites, as done by LNDD, would be around 7%. That is, LNDD would declare 7 of 100 known-clean samples to be doped.

The WADA criteria say the rate should be less than 1%. Duckstrap finds that using three of four would reduce the false positive rate down to 0.68%, and using all four shrinks the error to 0.06%. This means LNDD's use of two metabolites makes no sense, and violates the WADA testing standard of 1%.

By using either three or four metabolites criteria to meet the 1% false positive rate, Landis' results at LNDD would be negative.

Landis says he has scientists and documents showing his CIR test would have been considered negative at other WADA labs that use more stringent criteria than those apparently used by LNDD.

The T/E
The second charge is that Landis had a T/E ratio in excess of the allowed 4.0. This is the ratio of testosterone to epistestosterone, which should be close (around 1.0 +/- natural variance) in absence of doping. LNDD reported a measured ratio of 11.4 in a GC/MS IRMS confirmation test.

Duckstrap has previously argued that the T/E confirmation IRMS tests both seemed to have identified the peaks incorrectly (possibly due to Landis' legal cortisone). He found the TE using the peaks read a different way that should have been reported around 2.0, well within the legal limit.

The complication reading peaks is similar to the following situation. You pour some dry sand through a straw to form one peak. Then you move the straw over a tiny bit and pour even more sand to form another peak. Some of the sand spills over onto the first pile because they are so close together. How much sand is in the first pile? If you don't consider the spillover from the second, you can easily reach the wrong conclusion. The spillover from one pile to the other is called "elution". LNDD doesn't appear to have ever considered the effects of Landis's legal cortisone injections on the results. Duckstrap corrected for the cortisone, and sees no T/E violation.

Together...
Duckstrap makes plausible scientific arguments that LNDD has made the wrong call on both types of test -- better in fact than the slide show. If these are provable, at least to the "balance of probability" standard Landis must meet, these arguments may be good enough to comfortably take to a hearing, even for TBV.

The best detailed explanation of these arguments is at the Wiki.

Landis has hinted there is even more than this, but we have no idea what. Much more may not be needed.

[Darlene, you're the target audience for this explanation. Please let me know if you have trouble following it -- if not, I'll keep trying.]

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