Asking directly, because I could not find a straight answer: What a stability-indicating method is and how you demonstrate one
Posting a small dataset on stability-indicating method. It is mine, it is uncontrolled, and the method is stated so it can be discounted appropriately.
What I would like is not agreement but a second dataset collected by someone with no stake in mine. If one exists I would rather read it than argue for this one.
I had written a reply contradicting the opening post and deleted it. Here is what survived.
Linearity across the working range is a routine demonstration and it constrains how far a result can be extrapolated. A method linear from 80 to 120 per cent of nominal says nothing about a sample at ten per cent.
This is the version I would want a new member to read first.
Good question, well framed, and I would like to see it answered properly.
Post #2 is right about the mechanism and I think understates the practical bit.
Where a pharmacopoeial monograph exists, a method that follows it inherits a great deal of assurance. Almost nothing discussed here has one.
Adding the caveat now so it does not have to be extracted later.
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