Requirements change management based on object-oriented software engineering with unified modeling language

User requirements for software development are getting more complicated and are changing all the time. Not only should the requirements engineering process be well-organized but requirements change management should also be effective, especially for complex systems. However, the software engineering methodology employed can also make requirements change difficult to manage. Object-oriented software engineering using unified modeling language (UML) describes software systems by providing multiple views and diagrams. Therefore, software development with UML needs effective requirements change management. This study proposed a requirements change management model for object-oriented methodology with UML. In order to demonstrate the proposed model, business models from the selected case study, Mission Hospital Phuket, were chosen as the user requirements for the prototype system. Two aspects of the proposed system's performance were evaluated in the research laboratory: (1) users' expectation and (2) users' satisfaction.