Clinical and Laboratory Standards Institute document EP25-P--Evaluation of Stability of In Vitro Diagnostic Method Products; Proposed Guideline provides guidance and regression-based procedures for establishing stability-related claims of IVD method products such as reagent kits, calibrators, control products, and sample diluents. This guideline was written primarily for manufacturers and regulatory agencies, but also will be of interest to clinical laboratories. It provides information on the design, implementation, data analysis, and documentation needs for studies to establish and verify shelf life and in-use life of method products. Additional topics address assessment of product transport conditions on stability and accelerated stability testing.