On the Effort of Augmenting Use Cases with Screen Mockups: Results from a Preliminary Empirical Study

In order to increase stakeholders' comprehension on software requirements, Use Cases can be enhanced with screen mock-ups (i.e., GUI prototypes sketched with a special conceived graphical tool). However, the effort to write Use Cases augmented with screen mockups may increase, thus not justifying their adoption in the requirements engineering process. In this paper we present a preliminary empirical study to assess the effort needed to develop screen mockups. We first computed the time to define and design screen mockups and then we collected the subjects' perceptions about the effort to build them. Additionally, we collected also the subjects' perceptions about the tool used to produce screen mockups. The results indicate that the subjects: (i) perceive screen mockups construction as a non-onerous activity, (ii) believe that this activity requires a low effort as compared to the writing of Use Cases, and (iii) deem simple the use of the tool for sketching screen mockups.