Longitudinal associations between posttraumatic stress disorder, separation anxiety, and rumination among adolescents: Disentangling within-person and between-person associations.

Objective: Posttraumatic stress disorder (PTSD) and separation anxiety often show high comorbidity after trauma, which complicates the course of disease and treatment response. However, it is unclear how PTSD and separation anxiety comorbidity occur. According to the cognitive model of PTSD, rumination may be a key cognitive process linking the two constructs. Thus, this study aimed to examine the relation between PTSD and separation anxiety and to assess the mediating role of rumination in this relation among adolescents after trauma.

Method: A follow-up survey was conducted among 204 adolescent survivors of the Ya'an earthquake, at 6 months (T1), 12 months (T2), and 18 months (T3). A random-intercept cross-lagged panel model was used for data analysis to disentangle within-person dynamics from stable between-person differences.

Results: The results showed that at the within-person level, PTSD increased separation anxiety via rumination, and early PTSD further exacerbated later PTSD through increased rumination and separation anxiety.

Conclusions: These findings highlight the mediating role of rumination, elucidate the relation between PTSD and separation anxiety, and provide theoretical support for the development of transdiagnostic clinical interventions and treatments. (PsycInfo Database Record (c) 2025 APA, all rights reserved).