Posttraumatic Somatoform Dissociation in French Psychiatric Outpatients

Abstract

ABSTRACT Objective: Somatoform dissociative phenomena have long existed in psychiatric nosology but few quantitative data exist. This study aims at substantiating the association between trauma and somatoform dissociation, and presenting elements of validation of the French version of the Somatoform Dissociation Questionnaire (SDQ-20). Indeed, the SDQ-20 is a simple to use self-report questionnaire developed to quantify somatoform dissociative symptoms. Methods: One hundred forty psychiatric outpatients consecutively seen in the University Hospital in Tours, France were included, and completed the SDQ-20, the Dissociative Experiences Scale (DES), an inventory of traumatic experiences, and underwent a structured interview (CAPS) for diagnosis of Posttraumatic Stress Disorder (PTSD) according to the DSM-IV criteria. Results: We found a strong association between the SDQ-20 mean score and current PTSD or past PTSD. The Principal Components Analysis of this French version yielded a solution containing three factors: sensory neglect, subjective reactions to perceptive distortions, and vigilance modulation disturbance. The reliability of this French version was studied through the Cronbach's α coefficient (0.83). Both scales of dissociation used in our study (DES, SDQ-20) were shown to be highly correlated. Conclusion: This study confirms the strong association between trauma and dissociative symptoms as a whole, including somatoform dissociation. The SDQ-20 appeared to be a potentially useful screening instrument for dissociative disorders. It shed light on a “sub-dimension” of the dissociative phenomenon, when expressed in a somatic way.