In teacher education, case-based learning with text-based cases is an efficient method to foster pre-service teachers’ diagnostic competence. To adaptively utilize text-based cases, knowledge about effects of text characteristics and empathy on processing text-based diagnostic information is needed, but still scarce. Our study focuses on effects of two text characteristics, text style and text subject, and of empathy on the accuracy of case-based cognitive models. We examined this experimentally. 391 pre-service teachers read a case in psycho-narrative or externally focalised style (text style) about test anxiety or dyscalculia (text subject). We measured self-reported state- and trait-empathy and assessed cognitive models with a recognition and verification test. Regression analyses showed a main effect of text-style but not of text-subject, trait- and state-empathy, and moderation effects of text style and affective (but not cognitive) state-empathy. We draw implications for adaptively designing text-based cases and possible mechanisms of how empathy is involved in diagnostic judgement formation.