Abstracts

Bullying is a social and public health problem recognized across the globe. The aim with this thesis is to describe and understand bullying victimization of children and youth in a social-ecological perspective with the focus on prevalence, mental health, social relations and disclosing bullying victimization.This thesis includes four studies based on three different data sources: the parent-reported Nordic Study of Childrens Health and Wellbeing (NordChild, Studies I-II), interviews with Swedish youth (Study III) and the child-reported Swedish Health Behaviour in School-aged Children survey (HBSC, Study IV). As well as descriptive statistics, the data from NordChild was analysed with logistic regression (Studies I, II) and the HBCS data was analysed in a multi-level logistic regression. The interview study was based on grounded theory, analysed by two-step coding.The results of this thesis showed that parent-reported bullying victimization had decreased from 1996 (21.7 percent) to 2011 (19.2 percent) in the combined Nordic countries, but immigrant children were bullied more often than native children. Between 29.244.3 percent of the bullied children had mental health problems, varying between age and gender. A protective factor that gave higher odds of bullied children being mentally healthy was having several close friends. Not all parents knew whether their child was being bullied, and children with unclear status regarding whether they were being bullied had higher levels of mental health problems than non-victims. When bullied children disclosed victimization it was not simply a matter of telling or not telling, it was a circular process in transition between hidden and open victimization. Victims withheld disclosure of victimization for reasons associated with personal identity and/or reasons originating in distrust of adults. Bullied children, especially frequent victims, had higher odds of having poor relations with their parents and teachers than non-victims.The social-ecological perspective is used to understand the interplay between individual factors and the social context where the bullying exists. The results from the four studies is understood at different system levels; in the interaction with and between peers, family and school, and in interplay with norms and attitudes about victimization and bullying in the broader society.