[Context and motivation]
Case studies have the potential to be an essential bridge between the constructive (build new theories, algorithms, or methods to address practical problems) and the empirical (develop evidence through observation of or experience with existing methods or artifacts in practice) approaches to requirements engineering research.
To realize this potential, our aim is to provide representational guidance for designing a case study as a part of the invention process of a novel requirements engineering methodology (REM).
In this paper, we present the innovative use of assurance cases to emphasize argumentation and rigorous evidence planning during case study research design.
The steps involved in case study research design using the assurance case notation are outlined as a systematic way to plan a validation effort for a REM.