Objectives: To evaluate the relationship between systemic family dynamics and adolescent depression.Methods: An offline survey was distributed to 4,109 students in grades 6–12, with the final analysis including 3,014 students (1,524 boys and 1,490 girls) aged 10–18 years. The questionnaire included the Self-Rating Scale of Systemic Family Dynamics (SSFD), the Self-Rating Depression Scale (SDS), and demographic characteristics.Results: Family dynamics were negatively correlated with depressive symptoms, with better family dynamics (high scores) associated with lower levels of depression based on the SDS score. After adjusting for sociodemographic characteristics, an ordinal multiclass logistic regression analysis identified family atmosphere (OR = 0.952, 95% CI: 0.948–0.956, p < 0.001) as the most important protective family dynamic against depression, followed by individuality (OR = 0.964, 95% CI: 0.960–0.968, p < 0.001). Latent class analysis (LCA) created the low family dynamic and high family dynamic groups. There were significant differences in the mean SDS scores between the two groups (45.52 ± 10.57 vs. 53.78 ± 11.88; p < 0.001) that persisted after propensity matching. Family atmosphere and individuation had a favorable diagnostic value for depression, with AUCs of 0.778 (95% CI: 0.760–0.796) and 0.710 (95% CI: 0.690–0.730), respectively. The diagnostic models for depression performed well.Conclusion: Poor family dynamics may be responsible for adolescent depression. A variety of early intervention strategies focused on the family may potentially avoid adolescent depression.

The two-child policy has been implemented in China since 2016 and has attracted the attention of the world. Adolescents may face huge psychological challenges in the process of changing family structures and relationships. To date, no mental health survey of adolescents from two-child families has been conducted. We investigated the prevalence and risk factors for childhood trauma, anxiety, and depression in two-child families in a statistically representative sample of Chinese senior high school students from Shanghai. A total of 426 participants were randomly selected from 1,059 students of four senior high schools in different districts of Shanghai. The childhood trauma questionnaire-short form (CTQ-SF), self-rating anxiety scale (SAS) and self-rating depression scale (SDS) were used as the screening tools. We found that the overall prevalence of childhood trauma, anxiety, and depression among senior high school students in two-child families was 46.70% (95% CI, 39.93–53.47%), 22.17% (95% CI, 16.53–27.81%), and 35.85% (95% CI, 29.34–42.36%), respectively. The two-child families was an important factor associated childhood trauma, emotional neglect, and physical neglect (χ² = 5.984, p = 0.014; χ² = 4.071, p = 0.044; χ² = 4.202, p = 0.040). Ranking in two-child families was a risk factor for childhood trauma (β = −0.135, p = 0.048). Parental preference was a significantly correlated with physical abuse, physical neglect, anxiety, and depression (β = −1.581 to 0.088, p < 0.05). Meanwhile, emotional abuse, physical abuse, emotional neglect, and physical neglect of participants in the two groups were positively correlated with anxiety and depression (r = 0.195–0.478, p < 0.05). There was a significant relationship between sexual abuse and anxiety symptoms in the one-child family group (r = 0.161, p < 0.05). The findings suggest that the overall prevalence of childhood trauma, anxiety and depression among adolescents from two-child families in China was high. The two-child families and family ranking are important factors associated childhood trauma, while parental preference is related to anxiety and depression. These results highlight an urgent need to be addressed by adolescents' mental health service providers and policy-makers.

Background: To promote the balanced development with the population, China has phased out a one-child policy in 2016, and a two-child policy was launched, which has led to dramatic changes in family structure. The transition could be a huge challenge for adolescents who are in a period of psychological vulnerability. Purpose: This study explored the differences and predictors of family dynamics and functioning between two-child and one-child families in the context of China’s two-child policy. Methods: We used the Self-rating scale of Systemic Family Dynamics (SSFD) and Family Assessment Device-General Functioning (FAD-GF) to investigate the family dynamics, family functioning, and family structure and status of 3289 adolescents under the background of China’s two-child policy. Results: Results revealed that the mean scores for family atmosphere, personalization, disease concept, overall family dynamics, and family functioning health rate of the one-child families were higher than those of the two-child families. Parental marital status, mother’s education, annual household income, and family economic satisfaction in two-child and one-child families was positively correlated with family dynamics and functioning, but not significantly associated with living style, parental age and employment. Family financial satisfaction, parental marital status, and distress in the family were predictors of family dynamics and functioning, and parental preference was also an important factor in two-child families. Conclusion: The findings suggest family atmosphere, personality, disease concept, family dynamics, and family functioning of the one-child families were better than those of the two-child families. Unlike one-child families, parental preference is an important predictor of family dynamics and functioning in two child families. This study increases our understanding of adolescents psychological problems during family structure transitions under the background of fertility policy, providing psychologists with more evidence-based evidence and intervention directions.