Evaluate first prototype as quickly as possible in order to adjust the further development based on the results.
Carry out an early evaluation of a first prototype in order to obtain impressions, assessments regarding implementation of the story and fast results.
Story, motives, needs.
1-5 experts evaluate the prototype either simultaneously or successively and assess the interaction with it. It is recommended to consult different expert opinions:
The focus of the first user study lies on the comprehensibility of the interaction with the prototype within the framework, the story and the story board. The sample of users does not have to be large nor representative; instead it is more important to gather first impressions early on. Large effect sizes are of interest. A helpful method is "think aloud" where a study participant verbalizes all of the thoughts and actions during interaction. Afterwards, ask the users how they experienced the interaction. At this point, you can already evaluate whether the story has been implemented correctly into the prototype and if an experience as described in the story is indeed possible with the prototype.
Impressions of the first prototype, feedback for further development
When you evaluate a first prototype do not place priority on a random sample that is as large and representative as possible or on exact quantitative results, but on first impressions, assessments on the implementation of the story and fast results which in turn are built-upon for the further process.
Sarodnick, F., & Brau, H. (2006). Methoden der Usability Evaluation. Verlag Hans Huber. Field, A. P., & Hole, G. (2003). How to design and report experiments (p. 153). London: Sage publications