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

and other unmatched inter-group imbalance factors as independent variables. The value of ɑ is equal to 0.05. Results Sociodemographic characteristics The average age of the participants in this study was 12.49 ± 1.67 years. In the intervention group, the average number of activities per class was 14.81 (range: 10–29). Each class consisted of 4.38 posters on average, with minimum values of 2 posters and maximum values of 8 posters per class. Table 1 shows the distribution of sociodemographic characteristics between the interven- tion group and the control group. Significant differences were found in participants’ age, “rela- tionship between parents”, “relationship with father”, “father’s education level”, “parenting style”, and “family economic status” (P < 0.05). These unbalanced factors were controlled in the mixed model. Resilience changes in the intervention group and control group In this study, the demographic characteristics of the intervention group and the control group were significantly different (Table 1), and the changes in resilience of the two groups could not be directly compared. Therefore, the PSM method was used to match the data of the two groups, and the demographic characteristics of the two groups were comparable after match- ing (Table 2). After adjusting the confounding factors, the mixed linear model was fitted, and the results are shown in Table 3. Compared with the control group, the improvement of target focus, emotional control, interpersonal assistance and total mental resilience in the intervention

group was significant (P < 0.05). No significant difference in score changes were found between primary and secondary schools (P > 0.05). ICC, based on mixed model analysis, are presented in Table 3 to indicate clustering effects for the investigated outcomes. They were generally low and the highest clustering effects con- cerned total resilience, which was 0.034. Effects of intervention on resilience In the generalized linear mixed model, independent variables included intervention (peer edu- cation/control), age, “relationship between parents”, “relationship with father”, “father’s edu- cation level”, “parenting style”, and “family economic status”, with changes in resilience between baseline and final follow-up as the dependent variable and school as a random effect. Table 4 indicates that the intervention was effective for increasing the target focus (β = 0.893, SE = 0.282, P = 0.002), emotional adjustment (β = 1.766, SE = 0.389, P < 0.001), interpersonal assistance (β = 1.722, SE = 0.716, P = 0.016), and total resilience (β = 5.391, SE = 1.094, P < 0.001), but there were no significant differences in positive cognition and family support (P > 0.05). Table 4 shows sex differences in the effectiveness of the intervention. For boys, target focus (β = 0.882, SE = 0.425, P = 0.038), emotional adjustment (β = 1.935, SE = 0.445, P < 0.001), interpersonal assistance (β = 1.276, SE = 0.435, P = 0.004), and total resilience (β = 4.889, SE = 1.223, P < 0.001) were increased significantly. However, for girls, there were significant

improvements only in emotional adjustment (β = 1.625, SE = 0.439, P < 0.001), interpersonal assistance (β = 2.302, SE = 1.060, P = 0.030), and total resilience (β = 6.182, SE = 1.333, P < 0.001). 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 8 / 18