Joseph Coveney wrote:
>>My understanding is that clinical laboratory tests are typically set
up to be used such that a result's falling below the limit of
quantitation (LOQ) doesn't matter, so you never really hear much about
its being a problem in medicine. <<
This would be fine for any one test, but it's not what usually needs to
be done in envirometrics, where you often have a set of samples,
including NDs, and want to get an estimate of the mean (or median) level
of a particular analyte. There you need to pool the information on the
NDs. You can't just use medians, either, because the ND value can differ
for each observation.
(Yes, I am a psychometrician IRL but did some consulting in
envirometrics dealing with the issue of NDs and thus have a passing
knowledge of the literature, i.e., I've read a few books on the topic,
some articles and the EPA guidelines.)
I also agree with Nick's assessment that envirometrics would stand to
learn more from medical statistics than the other way around.
Jay
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