Schlosser, AnneAnneSchlosser0000-0002-7762-1142Paetsch, JenniferJenniferPaetsch0000-0001-8599-147X2023-02-082023-02-0820231664-1078https://fis.uni-bamberg.de/handle/uniba/58218Introduction: Teachers’ self-efficacy is an important indicator of student teachers’ preparedness for teaching. Interventions using video lessons are effective in increasing student teachers’ self-efficacy. However, there is a lack of research on emotional and reflective processes in the context of video-based interventions. Methods: The present study examined emotions and reflection as well as their effects on changes in self-efficacy in a video-based intervention. A total of 159 student teachers participated in the study. The participants were randomly assigned to three groups: Two groups analyzed video lessons in which group roup one received open-ended observation tasks (ig1) and group two received structured observation tasks (ig2). Participants in the control group (cg) analyzed text-based case studies with open-ended observation tasks. Results: The results show that self-efficacy increased with medium effect size (d = 0.68) in video group two (ig2), whose members analyzed videos using structured observation tasks but not in video group one (ig1), whose members analyzed open-ended observation tasks, and in the control group. In addition, there were significant relations between positive arousal and reflection. Finally, regression analyses showed that reflection was a significant predictor for changes in self-efficacy, whereas no significant effect of emotional arousal was detected. Discussion: In conclusion, the findings of this study indicate that video-based interventions with structured observation tasks increased self-efficacy among student teachers. Furthermore, the findings provide novel evidence on the association between reflection, self-efficacy and emotion in video-based interventions in teacher education.engself-efficacyemotionemotional arousalreflectionteacher educationvideo lessons370article10.3389/fpsyg.2023.1080883