(PS9-66) Necessary but not sufficient: The Role of Contrast Avoidance in Post-Traumatic Stress Disorder

Abstract Text:

Introduction:  Post-traumatic stress disorder (PTSD) is a prevalent mental health condition characterized by symptoms such as intrusive memories and emotional numbness, which often co-occur with other psychological disorders. The Contrast Avoidance Model, adopted from research into generalized anxiety disorder (GAD), may help elucidate potential transdiagnostic mechanisms. 

Methods:  Participants (N = 1,186) were recruited from Prolific and completed an online survey assessing demographic information, PTSD symptoms, and contrast avoidance (CA). Each participant reported at least one criterion A trauma. Latent class analysis (LCA) was performed to identify subgroups based on self-reported PTSD symptoms and CA. A random forest classification model was employed to predict class assignment using PTSD-specific and broader anxiety-related psychological indices.

Results:  Four classes of participants were labeled including a "Low PTSD and High CA" class, and a "High PTSD, High CA" class. The random forest model indicated high classification accuracy (i.e., sensitivity = 0.93; specificity = 0.96), and minimal overfitting. Variable importance rankings from a random forest model indicated that cognitive variables(e.g., negative beliefs about the world) were the most predictive of being classified into the "High PTSD and High CA class".


Conclusion: Elevated contrast avoidance is associated with higher PTSD symptoms. Whether contrast avoidance is a downstream consequence of PTSD symptoms or plays a role as a risk factor for higher PTSD symptoms can not be determined from the current study, but could be explored in future research. Negative beliefs about the world and negative cognitions of oneself were the highest predictors for elevated PTSD symptoms in those with high self-reported contrast avoidance compared to participants with high contrast avoidance and low PTSD symptoms.