Found here in the New York Times, is a thoughtful piece on how the anti doping labs are reacting to the Marion Jones A-B test imbroglio. It isn't common that the B test differs from the A test. Of course the biggest name is one of those.
Laboratories accredited by the World Anti-Doping Agency conducted about 183,000 drug tests last year. Of 3,909 positive A sample results, only three or four backup tests failed to confirm the initial finding, Dr. Olivier Rabin, science director for the antidoping agency, said in a telephone interview.
It is interesting that people ask 'what went wrong' in terms of not catching Jones. However, the question should be 'why did the results diverge. (I think the difference was the time delay; rhEPO is degraded by bacteria and enzymes in the urine).
Antidoping experts say there could be many reasons, aside from a lab error, why the backup analysis of Jones’s urine sample did not match the first result. The sample could have been collected incorrectly, packaged poorly or manipulated. The backup test could also have revealed such a slight margin between a negative and a positive that scientists could not confirm the initial finding...
Howard Jacobs, one of Jones’s lawyers, who has represented a number of high-profile athletes in doping cases, said he could think of only three reasons for the B sample result to differ from the A: a lab error, degradation of the urine samples or a problem with the test. He said he thinks the test for EPO is flawed.
Wonder if we will ever hear the full story?
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