Psychometric Properties of the 3-Item Clinician Administered Dissociative States Scale (CADSS)

Abstract

The 23-item Clinician Administered Dissociative States Scale (CADSS) has been widely used as a repeated measure of dissociative symptoms. A shortened version of the CADSS would be useful as a time-saving measure, especially for neurobiological studies of dissociation at multiple time points before and after an intervention. The purpose of this study was to assess the psychometric properties of two versions of a short form of the CADSS in a sample with and without posttraumatic stress disorder (PTSD). Participants with (N=200) and without (N=315) the diagnosis of PTSD were assessed with the 23-item CADSS and/or the 3-item CADSS, the 6-item CADSS, and other psychometric and neuropsychological assessments. Analyses were performed to examine internal consistency, validity as measured by correlation with measures of PTSD and trauma, and sensitivity to change following exposure to personalized scripts of traumatic memories. Both the 3-item CADSS (Cronbach’s alpha 0.82) and the 6-item CADSS (Cronbach’s alpha 0.81) showed good internal consistency. Validity for all versions was demonstrated based on correlations with other psychiatric symptom measures and ability to differentiate PTSD and non-PTSD participants. The 3-item CADSS demonstrated sensitivity to change based on a significant increase in scores after exposure to personalized traumatic scripts. Both short form versions of the CADSS have acceptable psychometric properties.