Examining the Effects of Alexithymia on the Relation Between Posttraumatic Stress Disorder and Over-Reporting

Objective: Empirical examinations of the relation between posttraumatic stress disorder (PTSD) and objective measures of symptom over-reporting may be useful for identification of mechanisms of this previously observed relation. The present study examined the moderating effect of alexithymia, defined as a deficit in the ability to identify and describe emotions, on the relation between PTSD and over-reporting. Method: Seventy-five veterans diagnosed with PTSD were recruited from an outpatient Veterans Affairs facility and the community. Participants were administered the Miller Forensic Assessment of Symptoms Test, along with the Toronto Alexithymia Scale and PTSD Checklist within a larger study of behavioral and physiological correlates of PTSD. Results: Hierarchical linear regression analyses showed a significant moderating effect of alexithymia, such that the relation between PTSD symptom severity and over-reporting was only significant in the presence of elevated alexithymia. Evaluation of the subscales of the Toronto Alexithymia Scale showed that the effect was greatest for the Difficulty Describing Emotions subscale. Conclusions: Alexithymia should be considered as a potential mechanism contributing to the over-reporting phenomena observed in the assessment and treatment of PTSD, and warrants further study. Brief interventions to improve understanding and description of emotional experiences may help to improve accuracy of symptom report.