System-approach methods for modeling and testing similarity of in vitro dissolutions of drug dosage formulations

System-approach based modeling methods are used to model dynamic systems describing in vitro dissolutions of drug dosage formulations. Employing the models of these systems, model-dependent criteria are proposed for testing similarity between in vitro dissolutions of different drug dosage formulations. The criteria proposed are exemplified and compared with the criterion called the similarity factor f(2), commonly used in the field of biomedicine. Advantages of the criteria proposed over this factor are presented.