In previous blogs we have provided explanation about robustness simulation in Fusion QbD and setting suitable distances between the single study factor levels.
As explained in these notes, for both topics we need to know the expected maximum variation of our study factors.
For this purpose, we usually refer to the vendor specification of the involved equipment and measuring devices.
But those specs usually do not directly report the value, that is required for our purpose. Therefore, we often receive questions of how to precisely set those values for individual parameters, especially if more than a single error source contributes to the overall analytical error (e.g. buffer concentration).
Especially for robustness simulation, we need to be as precise as possible with the expected analytical error.
Therefore, let us provide a little guidance of how to determine those values from vendor specs. Please also let us know, if you have particular method parameters, where you feel unsure about how to set this value. We will be happy to help.