Photo of Björn Sjögren

Björn Sjögren

Associate Professor

Peer Victimization and Bullying in School

Bullying in schools is a widespread phenomenon. My research focuses on using student surveys to map the prevalence of bullying and investigate how it relates to various cognitive, moral, and social factors. Together, our research group on bullying aims to contribute knowledge on how we can understand and prevent bullying in schools.

In most bullying situations, there are others present besides the perpetrators and the victims. My research has a particular focus on these bystander roles. Do bystanders take sides with the bullies, support the victims, or remain passive? And what factors influence these choices?


I primarily teach courses and programs for aspiring teachers, such as educational psychology, social relationships, and bullying, as well as scientific methodology.


Nordic Educational Research Association (NERA)
Bullying Research Network (BRNET)



Björn Sjögren, Robert Thornberg, Tiziana Pozzoli (2024) Reciprocal longitudinal associations of defender self-efficacy with defending and passive bystanding in peer victimization Psychology in the schools (Print) Continue to DOI
Robert Thornberg, Björn Sjögren, Gianluca Gini, Tiziana Pozzoli (2024) Testing the reciprocal longitudinal association between pro-aggressive bystander behavior and diffusion of responsibility in Swedish upper elementary school students Social Psychology of Education, Vol. 27, p. 215-235 Continue to DOI


Robert Thornberg, Linda Wänström, Björn Sjögren, Ylva Bjereld, Silvia Edling, Guadalupe Francia, Peter Gill (2023) A multilevel study of peer victimization and its associations with teacher support and well-functioning class climate Social Psychology of Education Continue to DOI
Camilla Forsberg, Björn Sjögren, Robert Thornberg, Jun Sung Hong, Claudio Longobardi (2023) Longitudinal reciprocal associations between student-teacher relationship quality and verbal and relational bullying victimization Social Psychology of Education Continue to DOI
Robert Thornberg, Björn Sjögren, Peter Ekberg, Sandra Englund, Trine Ohman, Bjorn Robbins (2023) Individual and collective moral disengagement as predictors of bullying perpetration: a short-term longitudinal multilevel study Educational Psychology, Vol. 43, p. 1219-1236 Continue to DOI