Assessing malingering and personality styles in dissociative identity disorder: A case study

Abstract

Dissociative identity disorder (DID), formerly known as multiple personality disorder, is characterised by two or more identities that control a patient’s actions, each typically with a distinct personal history, self-awareness, and name. They are believed to be the result of trauma-related dissociative defence mechanisms. Substantial progress has been made to determine the cognitive, neural, and psychometric signatures of dissociative identities. However, tools to discriminate genuine DID individuals from malingerers are still lacking. Here, we review the empirical attempts that have been made to detect malingerers of DID. Additionally, we present the case of a DID patient who exhibited nine different identities. After clinically ruling out malingering and factitious behaviour, we assessed her primary identity and two alternate identities (a trauma identity and an avoidant identity) using the Millon Index of Personality Styles. We found three very distinct personality profiles, with evident differences between primary and trauma identities. The profiles had high consistency scores and moderate to low negative and positive impression scores, respectively, thus supporting the profile’s validity for interpretation. Future studies should employ personality inventories that go beyond psychopathological symptoms to describe the consistency and adaptation style of dissociative identities when assessing malingering.