Authenticity in simulation-based learning is linked to cognitive processes implicated in learning. However, evidence on authenticity across formats is insufficient. We compared three case-based settings and investigated the effect of discontinuity in simulation on perceived authenticity. In a quasi-experiment, we compared formats of simulation in the context of medical education. All formats simulated anamnestic interviews with varying interactant and task representations using highly comparable designs. Interactants (patients) were simulated by (a) live actors (standardized patients), (b) live fellow students (roleplays), or (c) question menus and videoclips (virtual patients). The continuity of simulations varied. We measured perceived authenticity with three subscales: Realness, Involvement, and Spatial Presence. We employed confirmatory factor analysis (CFA) to assess measurement invariance across settings and analysis of variance on authenticity ratings to compare the effects of setting and discontinuous simulation. CFA supported the assumption of invariance. Settings differed in Realness and Spatial Presence but not Involvement. Discontinuous simulations yielded significantly lower ratings of authenticity than continuous simulations. The compared simulation modalities offer different advantages with respect to their perceived authenticity profiles. Lower levels of interactivity and reduced subtask representation do not necessarily lead to lower ratings of perceived authenticity. Spatial Presence can be as high for media-based simulation as for roleplays. Discontinuation of simulations by offering scaffolding impairs perceived authenticity. Scaffolds may be designed to avoid discontinuation of simulation to uphold perceived authenticity.