Thursday, January 31, 2008

Larry's Curb Your Anticipation, Part 12:
You should be able to argue...

Up to the Introduction; back to part 11 on to part 13.

By Commenter Larry

Now, some bullets about things you probably can argue, even if they may not be well received.


  • Can we use method validation criteria as criteria for the evaluation of the validity of a particular test result? For example, can we look at the difference between the original results of the FL stage 17 testing and the results from the subsequent EDF reprocessing, and say that this difference indicates a problem of repeatability or intermediate precision? This is a tricky question to answer. From our discussion above, we understand that criteria such as repeatability and intermediate precision are method validation criteria. Simply because a method produces a bad result does not mean that the method is invalid or should be reevaluated. However, we also understand that method validation is an ongoing process, and that a lab’s quality control efforts may indicate the need to revalidate a method. So it is important (perhaps even required under the ISL and ISO 17025) for a lab to review its test method results against the various method validation criteria, to see if revalidation of the method is necessary or advisable.

  • However, the failure of a particular lab result to comply with one or more method validation criteria does not necessarily mean that the result is invalid and should be thrown out. There is a difference between the criteria for evaluating test methods and the criteria for evaluating test results. To see this difference, all we need to do is to consider some of the method validation criteria discussed above. For example, the criterion of traceability addresses the test method only – either the method is tied to a known standard or it is not. The criterion of intermediate precision can be used to judge a test result only if the test is repeated at a different time or with different equipment or a different lab technician, but repeated testing of the same sample is not the norm.

  • Can the criteria for method validation be used by an athlete to prove an ISL departure? Absolutely. This was the basis for the argument made by Tyler Hamilton (discussed above) in his anti-doping case. It is an ISL departure if an AAF is based on a method that was not properly validated. However, we should recognize that it is a difficult proposition for an athlete to prove that a test method was not properly validated. Any such proof requires the athlete to challenge the science surrounding the test method, a tall order under the best of circumstances. This task is made even more difficult by the fact that the WADA rules presume the validity of all WADA lab methods, and that the documentation of the lab’s method validation will not be included in the lab document package provided to the athlete. This difficulty may be the reason why the FL team seemed to avoid many of the criteria discussed above (in particular, specificity) in the case it made before the arbitrators last year.

Up to the Introduction; back to part 11 on to part 13.