PTSD symptom changes during Trauma-Focused Cognitive Behavioural Therapy (TF-CBT) in children and adolescents: a Single-Case Experimental Design study

<b>Introduction:</b> Trauma-Focused Cognitive Behavioural Therapy (TF-CBT) is an evidence-based therapy for posttraumatic stress symptoms (PTSS) in children and adolescents. Nevertheless, drop-outs and limited effectiveness in individual and more complex cases remain a challenge. Detailed insight into individual symptom changes during therapy is missing. A Single-Case Experimental Design (SCED) is used to evaluate the changes and impact of the different modules of TF-CBT. <b>Methods:</b> A SCED study with repetitive baseline was conducted. The most prominent symptoms for each participant were assessed weekly throughout therapy. Standardized self-report questionnaires measured trauma, anxiety, depression, trauma-related cognitions, and parent–child interaction at six key points. Pre- and post-assessments were based on the clinician administrated interview. Session reports were used to evaluate the therapy's progress. <b>Results and Discussion:</b> Eight participants (ages 14–21) were included in the study. Graphical visualizations are presented of each individual symptom during the baseline and full course of the therapy (range = 20–70 weeks), alongside the corresponding standardized self-report. Most changes are seen during the narrative module, especially combined with the cognitive reprocessing and sharing module. A more severe or complex PTSD profile, needed more integration of coping skills and more sessions. For negative cognitions such as self-blame, cognitive reprocessing is necessary during the narrative. This SCED study provides a detailed insight in the therapeutic process of TF-CBT in a complex and heterogenous population. TF-CBT is effective in reducing trauma and comorbid symptoms, as observed in both individual and group changes. However, symptoms do not decrease in a clear line, and individual symptom fluctuations are common.The trauma narrative, combined with reprocessing and sharing modules, induces the most significant symptom changes.Individualized therapy adaptations, such as integrating coping skills and adopting a more flexible approach to cognitive restructuring, are necessary especially regarding children with a more complex trauma history or severity of symptoms.By focusing on in-therapy changes, we take a step towards personalized psychotherapy, supporting clinicians in making therapeutic adjustments and refining interventions. TF-CBT is effective in reducing trauma and comorbid symptoms, as observed in both individual and group changes. However, symptoms do not decrease in a clear line, and individual symptom fluctuations are common. The trauma narrative, combined with reprocessing and sharing modules, induces the most significant symptom changes. Individualized therapy adaptations, such as integrating coping skills and adopting a more flexible approach to cognitive restructuring, are necessary especially regarding children with a more complex trauma history or severity of symptoms. By focusing on in-therapy changes, we take a step towards personalized psychotherapy, supporting clinicians in making therapeutic adjustments and refining interventions.