On the subject in the title: Relative retention time as a better inter-laboratory comparator Working notes rather than a conclusion.
What changes if the standard account of relative retention time is wrong? I ask because I have been treating it as settled and I noticed this week that I could not say why.
Working through the consequences rather than the evidence, since others here are better placed on the evidence.
The limit of quantitation determines what the impurity table can honestly contain. Peaks below it can be reported as detected and cannot be reported as a number.
I have separated what I observed from what I concluded, which does not always happen.
Having read the whole relative retention time thread before replying: the question in the first post has not actually been answered yet, and three of us have answered a nearby one instead.
Building on post #6 rather than restating it.
Reporting a result to more decimal places than the method's precision supports is a small dishonesty that appears everywhere. A method with a two per cent relative standard deviation does not support a figure quoted to a hundredth.
The uncertainty is in the assumption, not in the calculation.
Read the full topic (12 posts)
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