Persona cases

Personas are a popular technique in User-Centered Design, however their validity can be called into question. While the techniques used to developed personas and their integration with other design activities provide some measure of validity, a persona's legitimacy can be threatened by challenging its characteristics. This note presents Persona Cases: personas whose characteristics are both grounded in, and traceable to their originating source of empirical data. This approach builds on the premise that sense-making in qualitative data analysis is an argumentative activity, and aligns concepts associated with a Grounded Theory analysis with recent work on arguing the characteristics of personas. We illustrate this approach using a case study in the Critical Infrastructure Protection domain.