Modelling a complex biological system: the human cardiovascular system — 2. Model validation, reduction and development

Abstract

Model valadity is a multi-faceted concept which is expressed as a set of validity criteria related to different modelling objectives. These criteria form the basis of a validation methodology for biological models - an integral part of the modelling methodology presented in the preceding paper. This is applied to the model of the human cardiovascular system. By means of model decomposition and reconstruction, validation occurs at a number of levels and includes empirical, theoretical and heuristic tests. In general, the model is shown to have reasonable validity in terms of its objectives; it is an adequate representation of the human cardiovascular system under certain conditions. Although some defects may be traced to the modelling of neural control, the model has an important role in the conception and testing of different hypotheses for such control. In conclusion, the two papers support the thesis that mathematical models, used wisely, are effective and necessary tools in complex systems research.