While a strength of Interactive Digital Narratives (IDN) is its support for multiperspectivity, this also poses a substantial challenge to its evaluation. Moreover, evaluation has to assess the system's ability to represent a complex reality as well as the user's understanding of that complex reality as a result of the experience of interacting with the system. This is needed to measure an IDN's efficiency and effectiveness in representing the chosen complex phenomenon. We here present some empirical methods employed by INDCOR members in their research including UX toolkits and scales. Particularly, we consider the impact of IDN on transformative learning and its evaluation through self-reporting and other alternatives.