IAAF Is Withholding Comment On Jones


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IAAF Is Withholding Comment On Jones

Postby gh » Thu Sep 07, 2006 10:36 am

But the headline on this story

<<IAAF wants to see results before clearing Jones>>

is a bit misleading, at least relative to the quotes from IAAF rep, which is the usual boilerplate in these cases of "we can't comment until the lab has reported to us."


http://sports.espn.go.com/oly/trackandf ... id=2577311
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Re: IAAF Is Withholding Comment On Jones

Postby TrakFan » Thu Sep 07, 2006 10:46 am

gh wrote:But the headline on this story

<<IAAF wants to see results before clearing Jones>>

is a bit misleading, at least relative to the quotes from IAAF rep, which is the usual boilerplate in these cases of "we can't comment until the lab has reported to us."


http://sports.espn.go.com/oly/trackandf ... id=2577311


Is that normal process? I would assume (perhaps, wrongly) that USADA would review the results and notify USATF/IAAF
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Postby gh » Thu Sep 07, 2006 11:00 am

I was just paraphrasing. Here's the precise quote

<<"We have not received any formal notification from the lab," International Association of Athletics Federation spokesman Nick Davies said Thursday. "Until then, we can't comment.">>

You're looking for a level of precision here I never intended, and neither did they. Bottom line, no matter what other links might be in the chain, is that IAAF needs to see whatever notification papers are part of the whole process. I have no idea what other alphabet bodies might sign off on it in transit.
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Postby tafnut » Thu Sep 07, 2006 12:06 pm

Obvious (i.e., stupid) question on my part:

What does this do to the credibility of WADA/UADA/IAAF/USATF?

How can anyone take anything seriously anymore?

a. A 'negative' test does not necessarily mean the athlete did NOT use a PED. He just didn't get caught.

b. A 'positive' test does not necessarily mean the athlete DID use a PED. The lab made an 'error'. [to what DO they ascribe Marion's +/- results?]


Good luck on this, ABC Boiz.
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Postby 26mi235 » Thu Sep 07, 2006 2:25 pm

tafnut wrote:Obvious (i.e., stupid) question on my part:

What does this do to the credibility of WADA/UADA/IAAF/USATF?

How can anyone take anything seriously anymore?

a. A 'negative' test does not necessarily mean the athlete did NOT use a PED. He just didn't get caught.

b. A 'positive' test does not necessarily mean the athlete DID use a PED. The lab made an 'error'. [to what DO they ascribe Marion's +/- results?]


Good luck on this, ABC Boiz.


You need better background on testing in a "statistical world". You want to both have a low likelihood of having a false positive and of having a false negative. One way to do this is to increase the sample size, which gets us to the A/B stuff. Another is the set of test charactreistics. A number of tests have large "regions" where the test is very likely + or -. This arises, for instance, when the standard error of the estimate is very small compared to the range of test values.

If the test value is determined "positive" with a value of 6 and the standard deviation/error is 0.5, then 6 works as a cutoff if a value in the range of 3-4 is thought to give a clear indication of doping use (and let us asume that the population average is 1.0 with a variation in the population of +/- 0.5 (0.5 is several (4?) standard deviations of a different distribution parameter than the standard error and is why I used 3-4 rather than 4 or three because we have a variation in the true level that reflects doping). If you increase the precision to 0.05, you can probably cut your critical value for the test down to 4.0 or just above. With this smaller SD you will have cut down substantially on the false negatives by moving the standard while still doing better on false positives. I suspect that t/e ratios are like this but there is the complication that both t and e are involved with "random terms"; the values used in the example are also genreally consistent with the testosterone test.

EPO has a relatively "big" "standard error" in the sense discussed above; in addition, it is not a 'univariate' test but one with blotches and other messy things. There are lots of places where errors can be made, since there are a lot of steps. Many (but not necessarily most) errors would likely lead to greater difficulty in detecting EPO through the test (this is the argument made by some in the supposed LA tests of the "B" samples for EPO when they had not been tested for EPO before and had been frozen for five or six years).

Sorry this is not better constructed and/or thought out/corrected, but I am hurried at work.
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Postby Snation » Thu Sep 07, 2006 6:21 pm

Does the Jones case affect the credibility of the various organizations responsible for testing?

No this doesn't affect the credibility of those orgs. It should give people pause about jumping to conclusions based on one result. And it should give warning to organizations not to leak 'A' results. I think it is 80/20 or 90/10 that Jones is a drug cheat. However, I also think that her confidentiality should be maintained.

Fans should realize there is nothing 100% or 0%.

It isn't easy to understand the tests. Very technical. For instance the EPO test uses a form of gel elctrophoresis. EPO and rhEPO have the same protein sequence, but different sugars attached. Thus a lab can identify the rhEPO form by seperating out the proteins from other stuff in urine, then using chemiluminiscence to identify 'bands' on the 'proteins'. (I believe using an antibody). The distinction is made by visual inspection.

There are lots of pitfalls along the way. The urine needs to be superconcentrated. Enzymes in the urine can degrade the proteins. etc.

It was thought that if A and B samples were positive, the that was a true+; however there is now debate on one possible false +.

You can also see that perhaps testing A and B samples weeks apart might lead to some problems. I don't know that for a fact.

The T:E ratio, relies on Mass Spectrometry(IRMS), where quantitative levels of T and E are determined.

The mean T:E is 1.33 +/- 0.86. That means 67% of the population is within one SD (0.47 to 2.19); 95% of the population is with 2SD -0.61 to 3.15; and 99.7% of the population is within 3SD -1.47 to 4.01. (if this is a normal distribution - a bell curve).

So you can see that if you are in the top 0.15% percents, you could have a 'false positive' T:E ratio, in other words the lab could report you as abnormal (taking something to screw up the ratio), when you had an abnornally high ratio based on your biology.

Thus this test is preliminary to to a GC-IRMS to detect synthetic carbons on the T.

Other foreign substances are detected by HPPLC or High Res MS. There isn't much need to determine mean and SD since your endogenous nandrolone level should be 0.
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Of course there can be monkey business, even in the lab. Poisoned vials. Contamination. Malfunctions on machines. Mixups in specimen handling.

And that is why it is never 100% or 0%.
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Postby 26mi235 » Fri Sep 08, 2006 5:13 am

Thank you, Snation
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