The effect of peer education based on adolescent health education on the resilience of children and adolescents: A cluster randomized controlled trial

discussion, sitcom performance, and poster design can increase the opportunity for communi- cation with peers, raising team awareness. These benefits may be the reason for increased interpersonal assistance. In particular, no significant improvement was found in positive cog- nition and family support in our study. The reasons may be that our intervention mainly involves adolescent health education and positive coping styles, with less positive cognition toward difficulties and family support, which also suggests that more attention should be devoted to these two dimensions. In terms of total resilience, we found that, in the absence of intervention measures, the con- trol group of students’ resilience decreased, while the resilience of the intervention group sig- nificantly improved after peer education. In other words, peer education intervention based on adolescent health education could weaken the negative impacts of adolescent upheavals on the resilience of adolescents and even reverse the developmental trajectory of young people’s mental resilience. This further demonstrates that peer education of resilience for children and adolescents is successful by taking physiological knowledge, mental health education and healthy lifestyle as targeted interventions. Adolescence serves as a transitional period and can be "leveraged to encourage positive development trajectories" through interventions [63], such as peer intervention, individual and group psychological interventions, and school and com- munity projects [12, 64], to support adolescent resilience.

Gender differences are also a cause for concern. Significant gender differences have been shown to exist in potentially traumatic events and subsequent posttraumatic stress disorder [65], and other studies have found that women are more likely to develop mental or physical problems in response to life stresses or potentially traumatic events [66–68]. In other words, the psychological problems of girls are more difficult to intervene than those of men. Our results also indicate gender differences in the effectiveness of resilience interventions, with more effectiveness for males than for females. The intervention effect of male students is mainly reflected in goal focus, emotion control, interpersonal assistance and total resilience, while that of female students is mainly reflected in emotion control, interpersonal assistance, and total resilience. It follows that the intervention of goal focus is easier for men than for women. The effect of clustering must be taken into account in the results. The intra-cluster correla- tion coefficient (ICC) is the proportion of the total variance of the results that can be explained by inter-cluster differences, and is often used to estimate the clustering effect of an experiment [41]. In this study, the ICC of the main outcome variables were all less than 0.05. On the one hand, the ICC value is smaller than the ICC size assumed when calculating the sample size, indicating that the actual sample size of this study meets the requirements. On the other hand,

the small ICC indicates that the difference in outcome between the intervention group and the control group is mainly caused by peer education, rather than inter-group differences, and peer education is effective in the intervention of mental resilience. In addition, it can provide information for future cluster trials in similar environment. Many mental health disorders emerge in late childhood and early adolescence and impose a burden of these disorders on young people and later in life [69]. In 2019, China’s Ministry of Education and 10 other government departments launched a joint action plan to pay special attention to the mental health of children and adolescents. According to the action plan, schools at all levels and of all types should establish psychological service platforms to provide mental health services for students by 2022 [2]. Schools play an important role in the transition of children and adolescents to adulthood. Although many schools provide basic health infor- mation and education to adolescents, teaching methods seem ineffective due to a number of factors, including culture, religion and belief. The results of this study emphasize that policy makers should attach importance to supporting the implementation and development of PLOS ONE The effect of peer education based on adolescent health education on resilience of children and adolescents PLOS ONE | https://doi.org/10.1371/journal.pone.0263012 February 2, 2022 13 / 18