3rd class medical urinalysis?

"Gig 601XL Builder" wrDOTgiaconaATsuddenlink.net wrote:

You are right about the tests failing. Especially the quick tests. They
fail at a rate close to 50% both false positives and negatives that's why
we stopped using them. We use a lab with a mass spectrometer that could
probably tell what you had for dinner last Thursday. And a positive is a
positive only after a medical review officer talks to the tested
individual and finds out all the legal substances that they could have
ingested that might give a false positive.

I know this is getting out of the aviation thing; but, if these
advanced techniques you mention are so refined, how comes we often
hear about problems with professional athletes being falsely accused
of doping? Since there is a lot of money at stake, I wouldn't think
they go for the cheap version of the tests; pro athletes are surrounded
by physicians who should know better about what substances might or might
not cause a problem; the whole thing about chain of custody of the
samples should be taken care of very carefully because of they are under
a lot of scrutiny, etc. So, if they can't seem to get it right in such
a context, why should I trust my hypothetical employer on this issue?

(note that my current employer doesn't require such a test -- I don't
have teen age kids, and only smoked the thing where it was legal to do
so)

--Sylvain