Teacher autonomy support reduces adolescent anxiety and depression: An 18-month longitudinal study.

Grounded in stage-environment fit theory, this study adopts a longitudinal design to examine the contribution of autonomy support from teachers to reducing adolescent anxiety and depression. A total of 236 Chinese adolescents (57.38% females, Mage = 14.34) completed questionnaires on teacher autonomy support, basic psychological needs satisfaction, school engagement, anxiety, and depression in the fall and spring semesters of their 7th and 8th grade years. The results showed that teacher autonomy support in the fall of 7th grade boosted basic psychological needs satisfaction in the spring of 7th grade; this, in turn, increased school engagement in the fall of 8th grade, which subsequently decreased anxiety and depression in the spring of 8th grade. These findings demonstrated the significant effect of teacher autonomy support on reducing adolescent anxiety and depression; furthermore, it highlighted the mediating roles of basic psychological needs satisfaction and school engagement in this relationship.