Students who have repeated a grade have higher risks of being victims of bullying in countries around the world, according to a new study of nearly half a million students publishing November 11^th in PLOS Medicine by Xiayun Zuo of Fudan University, China, and colleagues. The study is a part of the PLOS Medicine Special Issue on Global Child Health.

Addressing and preventing school violence, including bullying, is a specific target of the United National Sustainable Development Goals. Few studies involving large samples have examined the association between grade repetition and bullying victimization. In the new study, researchers used data from the Program for International Student Assessment (PIA) 2018, which included information on 465,146 students aged 15 and 16 from 74 countries/economies.

Overall, 12.25% of included students had repeated a grade and 30.32% of students reported having experienced bullying at least a few times a month during the previous year. Students who had repeated a grade were more likely to have been the victim of bullying compared to their peers (OR 95% CI 1.32-1.52, p<0.001). The association was observed for students in 46 different countries/economies, and in students of both sexes. Compared to boys, however, girls who repeated a grade had higher risks of being made fun of, being threatened, having possessions taken away, and being pushed around.

The authors note that while the findings support a relationship between the experiences of repeating a grade and bullying victimization, the cross-sectional study cannot determine if such a relationship is causal, or the direction of the relationship. The study was also limited to adolescents who were attending school at the time the survey was administered, and the measures of bullying experiences and grade repetition were self-reported.

"These results are of great concern for parents, teachers, principals, and policymakers at different levels, especially in countries where grade repetition is particularly prevalent," the authors say. "Grade repetition is associated with bullying victimization in both boys and girls."