Revisiting: Spike-and-recover accuracy for a peptide assay — setting out what I have, and where I think it stops being reliable.
I was wrong about Spike-and-recover accuracy in a thread last spring and I would like to correct it publicly rather than quietly.
The error was in the units, which changed the conclusion by an order of magnitude. Setting out the corrected version, and the way I now check for that class of mistake.
Limits of detection and quantitation: LOD is the lowest concentration that produces a signal above background. LOQ is the lowest concentration at which the method meets precision and accuracy acceptance criteria. Both are determined empirically.
That is my reading. Someone else read the same page differently and was reasonable.
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