Theses Doctoral

Understanding isolated and non-isolated victims of peer victimization in middle school

Aoki, Sayaka

The purpose of this study was to increase the understanding of the differences between isolated and non-isolated victims of peer victimization (PV) in middle school, in order to better understand the diverse mechanisms underlying the development of PV and to apply such knowledge to intervention programs for different types of victims. To meet this purpose, two research questions (RQ) were proposed. The first RQ examined how the relationship between self-reported PV and its risk factors/concurrent correlates (individual characteristics, such as peer-reported aggression, shyness, as well as self-reported internalizing problems and social skills, and patterns in peer relationships, such as peer-reported rejection by boys/girls and likelihood of having a mutually liked peer) are different depending on the level of peer-rated isolation in the 7th grade. The second RQ investigated factors associated with a decrease in peer victimization in the following year (8th grade), and examined whether such factors are different for isolated victims and non-isolated victims.
To address these research questions, secondary analyses were conducted on the data gathered by Brassard and colleagues in 3-year longitudinal survey conducted with the entire cohort of students in two middle schools in a lower income, racially heterogeneous urban school district. Participants were 640 students whose PV and isolation data in the 7th grade were available. PV was measured using the Social Experience Questionnaire (Crick & Glotpeter, 1996). Isolation was calculated based on peer nomination on an item, "play alone," from the Revised Class Play (Masten, Morison, & Pellegrini, 1985).
The results of the analyses indicated that non-isolated victims were not as different from isolated victims as expected. However, isolated victims and non-isolated victims were found to be two distinct groups of victims confronted with different challenges. Isolated victims, specifically isolated victimized boys, had poorer peer relationship patterns, including higher rejection by boys and girls, and lower likelihood of having a mutually-liked peer, while non-isolated victims suffered more from internalizing problems. Meanwhile, some similarities were found between these two types of victims; both of them are less shy and have fewer social skills compared to the non-victimized counterparts. PV was not significantly related to aggression for either isolated participants or non-isolated participants.
This study also identified possible individual characteristics that are related to a decrease in PV in a following year. Shyness was associated with escape from victimization for both non-isolated victims and isolated victims as was low internalizing problems for isolated victims.
These findings have implications for practices in school and clinical settings, including the importance of social skill training as an attempt to prevent adolescents from suffering from PV, and prioritization of clinical services for isolated victims to reduce their internalizing problems. This study also suggested some directions for future studies, including comparing isolated victims and non-isolated victims in more diverse aspects of peer relationships (e.g., popularity and friends' characteristics) , a more comprehensive analysis for the relationship between shyness and PV, and the identification of social skills that are beneficial for different types of victims.


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More About This Work

Academic Units
School Psychology
Thesis Advisors
Brassard, Marla
Ph.D., Columbia University
Published Here
July 7, 2014