Peer Bullying Victimization Trajectories for Sexually and Gender Diverse Youth from Early Childhood to Late Adolescence.

Sexually and gender diverse (SGD) youth experience more peer bullying victimization than heterosexual, cisgender youth during adolescence, yet the emergence and persistence of these disparities remain underexplored. Also, it is unclear which factors are associated with these disparities across development, and how these disparities are linked to late adolescent health discrepancies. This study utilized the sample from the Millennium Cohort Study in Britain (N = 10,080; 51.3% assigned female at birth; M = 2.28, SD = 0.46 at Wave 2), in which 23.74% of youth reported non-heterosexual attraction, 21.59% reported non-heterosexual identity, and 1.08% reported gender identity not in line with the sex assigned at birth. Using latent class growth modeling, four peer bullying victimization trajectories were identified, with early peak (7.2%), late childhood peak (6.3%), adolescence onset (12.8%), and low (73.6%) rates of victimization. SGD youth, compared to heterosexual and cisgender youth, were found to have increased odds of being in the victimization-involved classes, especially the adolescence onset class. The study further revealed that SGD youth reported more mental health and relational difficulties in childhood, which were linked to their heightened risk of longer-lasting victimization. Further, long-term victimization was found to partially account for the disparities in health and well-being for SGD youth in late adolescence. In conclusion, SGD youth were more likely to experience longer-lasting bullying victimization during childhood and adolescence, its related mental and relational vulnerabilities were already established in childhood, and such victimization disparities were further linked to their detrimental health and well-being in late adolescence. The design, hypotheses, and target analyses of the current study were preregistered on 21st April 2023 at https://osf.io/f2zxy .