The Potential Effectiveness of an Online Gender-Based Violence Prevention Program for European Students—The Role of Gender Essentialism, Ambivalent Sexism, and Perceived Responsiveness of the University

: This study evaluates the potential effectiveness of an online course concerning gender-based violence prevention, which combines the bystander intervention approach and the myths-based approach. The sample consists of 67 students who participated in three measurements-before the course, immediately after the course, and 3 months later. Gender-based violence myth acceptance decreased, and bystander efficacy increased after the course. The effects were the strongest among people with high ambivalent sexism and gender essentialism. The results suggest that the course was effective; however, a replication on a bigger and more diverse sample is needed.