Impact of ideal levels on depressive symptoms among high school students and mediating role of frustration tolerance: a prospective cohort study

The mental health problems among senior high school students require urgent attention in recent years. Ideal level, as an essential psychological quality, its long-term impact on depressive emotions remains unclear, and the mediating role of frustration tolerance between these 2 factors still lacks prospective evidence. This study aims to determine the predictive effect of ideal level on depressive symptoms and the mediating mechanism of frustration tolerance among high school students in Chongqing.

This study adopted a prospective cohort design. A total of 308 high school students from 3 high schools in Chongqing were surveyed at 3 time points: T1 (November 2024), T2 (May 2025), and T3 (November 2025). Revised Contemporary Adolescent Ideal Questionnaire, Frustration Tolerance Scale for Students, and Patient Health Questionnaire-9 were used to assess the levels of ideal, frustration tolerance, and depressive symptoms, respectively. Descriptive analysis, correlation analysis, cross-lagged analysis, and structural equation modeling were performed on the questionnaire data.

① High school students demonstrated relatively high ideal levels, with a total score of 154. 28±13. 68, which remained stable over 1 year. The frustration tolerance scores were 61. 77±14. 39 at baseline and increased progressively to 65. 83±15. 68 after 1 year (P<0. 001). The depressive symptom scores were 1. 23±2. 45 at baseline and elevated significantly to 4. 79±4. 33 after 1 year (P<0. 001). The career ideal scores were higher in 16-year-old adolescents than in 15-year-old counterparts (P<0. 05), and the male students had higher total frustration tolerance scores than the female (P<0. 01). ② The ideal level was positively correlated with frustration tolerance (r=0. 17 to 0. 30, P<0. 01), and both were negatively correlated with depressive symptoms (r=-0. 23 to -0. 15, P<0. 01). ③ The results from the cross-lagged model indicated that ideal level positively predicted frustration tolerance levels at 6 months later (β =0. 10, P<0. 01). ④ Frustration tolerance played a fully mediating role between ideal level and depressive symptom scores (β=-0. 07, 95%CI: -0. 19 to -0. 02, P<0. 01), with the total indirect effect of the chain mediation accounting for 8. 24% of the total effect.

Ideal level in high school students positively predicts frustration tolerance, and frustration tolerance plays a fully mediating role between ideal level and depressive symptoms. It is recommended that families, schools, and communities seize the critical period of ideal formation to strengthen frustration tolerance training, thereby reducing depressive symptoms and laying a foundation for achieving national strategic goals.