Abstract
The knowledge of the robustness/ruggedness of analytical processes is an essential feature in the analytical validation. The definitions and the different aims of such studies are given. A dual general procedure for checking robustness/ruggedness in both intrinsic and extrinsic validation is presented and the different steps are discussed. The denomination of “inertia study” is introduced to designate this methodology in extrinsic validation and precision and trueness tests are proposed inside the inertia study. Several experimental designs, depending on the goal of robustness/ruggedness study and the type of variables (quantitative or qualitative) are considered.