Understandability in class diagrams

Understandability of class diagrams is a quality attribute that should be evaluated, due to the importance of class diagrams for the design of software products and for product management when continuous improvement is of importance for an organization. However, the evaluation of class diagrams is a difficult task if the understandability concept itself is not understood. Furthermore, software products most of the times are evaluated after the system is finished. This work proposes an understandability quality model that is reusable, extensible and customizable. It may be used as a guide to evaluate the class diagrams before starting the implementation phase of software systems. After the validation of the model, it was found that the model is highly prescriptive so areas for improvement in the class diagrams are detected straightforward.