A review of the impact on XP methodology of business model inclusion in requirements elicitation

XP (eXtreme Programming) agile methodology uses the User Stories as a requirements elicitation strategy. The user stories are based on natural language, which may cause some misunderstanding and miscomprehension problems between software development team and stakeholders. The paper proposes the inclusion of Business Process Models (BPN) in the XP methodology as an alternative to user stories, seeking to improve the quality and quantity of the information collected. The proposal was evaluated using user stories vs. BPN in 11 projects during all phases proposed by XP. Both strategies –and their effectiveness– were analyzed through software metrics, in order to demonstrate the improvement in the development process. By applying software metrics, it was shown that the use of BPN: improves communication between analysts and others involved, increase approval rate of customer requirements, shortens delivery requirement, fewer changes are made in each iteration and a lower percentage of defects are found by the stakeholder, regarding the use of user stories.