There have been many different approaches to building health care models. Because of these differences, it is sometimes difficult to relate the developed models to each other. 

We have therefore first defined the submodels of the health care system and clarified the relation of our approach to studies already undertaken. The submodels also show the steps in building the health care model. 

The first step was to construct the morbidity model of degenerative diseases. The validity of the model was tested for various countries, using statistics from the World Health Organization. The fit of the model to empirical data was satisfactory. The model was applied to an international comparison and estimation of trends in degenerative diseases. The study showed the feasibility of this type of approach in health planning.