These terms are referred to as "analytical perform­ ance parameters" or sometimes as "analytical figures of merit/' Most of these terms are familiar and are used daily in the laboratory. However, some may mean dif­ ferent things to different people. To avoid confusion, therefore, it is necessary to have a complete understand­ ing of the terminology and definitions. Recognizing this, one of the first harmonization projects taken up by the ICH was the development of the guideline "Validation of Analytical Methods: Definitions and Terminology." ICH divided the validation characteristics somewhat differ­ ently, as outlined in Figure 4.