Gender differences in school environment and depressive symptoms in Chinese adolescents: The multilevel mediating role of peer support

Depressive symptoms pose significant health challenges to adolescent development worldwide. In the ecological systems framework, factors within the microsystem, like the school environment, can directly relate to individual psychological health. Given group-level nature of school environment, this relationship is inherently multilevel: the collective dimension of school environment provides a shared context that reflects cumulative school-wide factors, which, in turn, are linked to individual outcomes. While previous research explored the direct link between school environment and depressive symptoms, much less is known about the multilevel mediating mechanisms involved. This cross-sectional study utilized a dataset from 13,239 adolescents (50.8 % female; Mage = 13.435, SD = 0.964) across 85 Chinese schools collected in 2021–2022. Based on Multilevel Structural Equation Modeling (MSEM) with random slopes, a 2–1-1 multilevel mediating model was employed to investigate peer support’s mediating role between group-level school environment and depressive symptoms. Results showed a negative association between group-level school environment and depressive symptoms, mediated by peer support. Gender differences revealed stronger direct and indirect correlations for females. The findings emphasize fostering positive broad school environments and promoting individual peer support in combatting depressive symptoms, especially for female adolescents.