Abstract:
The inclusion of the dissociative subtype of post-traumatic stress
disorder (PTSD-DS) in the fifth edition of the Diagnostic and
Statistical Manual of Mental Disorders (DSM–5) reflects the importance
of assessing PTSD-DS. We developed the Dissociative
Subtype of PTSD Interview (DSP-I). This clinician-administered
instrument assesses the presence and severity of PTSD-DS (i.e.,
symptoms of depersonalization or derealization) and contains a
supplementary checklist that enables assessment and differentiation
of other trauma-related dissociative symptoms (i.e., blanking
out, emotional numbing, alterations in sensory perception, amnesia,
and identity confusion). The psychometric properties were
tested in 131 treatment-seeking individuals with PTSD and histories
of multiple trauma, 17.6 % of whom met criteria for PTSDDS
in accordance with the DSP-I. The checklist was tested in 275
treatment-seeking individuals. Results showed the DSP-I to have
high internal consistency, good convergent validity with PTSD-DS
items of the CAPS-5, and good divergent validity with scales of
somatization, anxiety and depression. The depersonalization and
derealization scales were highly associated. Moreover, the DSP-I
accounted for an additional variance in PTSD severity scores of
8% over and above the CAPS-5 and number of traumatic experiences.
The dissociative experiences of the checklist were more
strongly associated with scales of overall distress, somatization,
depression, and anxiety than scales of depersonalization and
derealization. In conclusion, the DSP-I appears to be a clinically
relevant and psychometrically sound instrument that is valuable
for use in clinical and research settings.