“As an undergraduate student in psychology, I was taught that multiple personalities were a very rare and bizarre disorder. That is all that I was taught on ... It soon became apparent that what I had been taught was simply not true. Not only was I meeting people with multiplicity; these individuals entering my life were normal human beings with much to offer. They were simply people who had endured more than their share of pain in this life and were struggling to make sense of it.”
― Deborah Bray Haddock, The Dissociative Identity Disorder Sourcebook
Boon, S. & Draijer, N. (1993). The differentiation of patients with MPD or DDNOS from patients with a cluster B personality disorder. Dissociation, 6(2/3), 126-135. doi:10.1300/J229v07n02_06
Abstract: Because of similarities in presentation, multiple personality disorder (MPD) and dissociative disorder not otherwise specified (DDNOS) can be misdiagnosed as borderline personality disorder (BPD) or another cluster B personality disorder. In order to find distinguishing symptoms, four groups of patients are compared: DDNOS patients (N=24); MPD patients (N=49); patients with BPD or histrionic personality disorder, referred for evaluation of dissociative pathology (N=21); control patients with a cluster B personality disorder (N=19). All patients were interviewed with the Structured Clinical Interview for DSM-III-R Dissociative Disorders (SCID-D) and the Structured Trauma Interview (STI).
Although there are many areas of overlap in the phenomenology of patients with MPD or DDNOS and patients with a "cluster B" personality disorder, we clearly found that these groups can be differentiated by the severity and cluster of dissociative symptoms, the prevalence of some Schneiderian symptoms, and the severity of childhood trauma.
Dell, P. F. (2006). The multidimensional inventory of dissociation (MID): A comprehensive measure of pathological dissociation. Journal of Trauma & Dissociation, 7(2), 77-106. doi:10.1300/J229v07n02_06
Abstract: This article describes the development and validation of the Multidimensional Inventory of Dissociation (MID). The MID is a 218-item, self-administered, multiscale instrument that comprehensively assesses the phenomenological domain of pathological dissociation and diagnoses the dissociative disorders. The MID measures 14 major facets of pathological dissociation; it has 23 dissociation diagnostic scales that simultaneously operationalize (1) the subjective/ phenomenological domain of pathological dissociation and (2) the hypothesized dissociative symptoms of dissociative identity disorder (Dell, 2001a). The MID was designed for clinical research and for diagnostic assessment of patients who present with a mixture of dissociative, posttraumatic, and borderline symptoms. The MID demonstrated internal reliability, temporal stability, convergent validity, discriminant validity, and construct validity. The MID also exhibited incremental validity over the Dissociative Experiences Scale (DES) by predicting an additional 18% of the variance in weighted abuse scores on the Traumatic Experiences Questionnaire (TEQ). Confirmatory factor analysis (CFA) did not support a one-factor model of the MID's clinical scales (i.e., the 14 facets and the 23 diagnostic symptoms). In contrast, however, CFA of the MID's factor scales (Dell & Lawson, 2005) has strongly supported a one-factor model. It was concluded that both the MID's 168 dissociation items and the construct of pathological dissociation have a second-order, unifactorial structure.
Franklin, J. (1988). Diagnosis of covert and subtle forms of multiple personality disorder through dissociative signs. Dissociation, 1(2), 27-33.
Abstract: There are different forms of multiple personality disorder (MPD) that vary on a dissociative continuum from subtle forms in which the alters are not very distinct or elaborated and often influence each other without assuming full control, to patients with fully developed MPD, whose alters are distinct, elaborated, assume full control, and emerge overtly. Most MPD patients present covertly, and some patients with covert presentations will later show overt classic symptoms, while those with subtle forms will often remain mild and subdued. Most MPD patients hide or disguise their condition, while their alters express their thoughts and feelings through subtle dissociative signs that occur when the alters influence each other, partly emerge, or subtly shift. These signs consist of frequent, sometimes sudden, fluctuations in affects, thoughts and behaviors, transferences, developmental levels, and psychiatric symptoms, and marked discrepancies in memories, viewpoint, and attitudes, which may indicate the possible presence of alters and of MPD or Dissociative Disorder Not Otherwise specified: variants of MPD. The case of a subtle form of MPD is presented which illustrates some of the subtle signs of dissociation and other dissociative symptoms often seen in these patients.
Hall, P., & Steinberg, M. (1994). Systematic assessment of dissociative symptoms and disorders using the SCID-D in a clinical outpatient setting: Three cases. Dissociation, 7(2), 112-116.
Abstract: This paper presents three case studies illustrating the range and scope of the clinical applications of the SCID-D, a semi-structured interview for the assessment and diagnosis of dissociative symptoms and disorders according to DSM-IV criteria. The studies indicate the effectiveness of the SCID-D in differential diagnosis between medical and psychiatric conditions, in symptom documentation for forensic cases, and in treatment planning for patients previously diagnosed with dissociative identity disorder (DID), formerly multiple personality disorder (MPD), who are experiencing impasses in therapy. Although the SCID-D is not a trauma questionnaire, its ability to elicit spontaneous descriptions of trauma from patients without the use of leading or intrusive questions makes it a valuable instrument for diagnosis and assessment as well as treatment planning and implementation. Early diagnosis of dissociative disorders with the SCID-D can lead to timely and effective treatment for those suffering from DID and the dissociative disorders.
Ijzendoorn, M. H., & Schuengel, C. (1996). The measurement of dissociation in normal and clinical populations: Meta-analytic validation of the Dissociative Experiences Scale (DES). Clinical Psychology Review, 16(5), 365-382. doi:10.1016/0272-7358(96)00006-2
Abstract: The Dissociative Experiences Scale (DES) has now been used in over 100 studies on dissociation. This article reports on a series of meta-analyses to test some of the theoretical assumptions underlying the DES and to examine the instrument's reliability and validity. Studies wilh the DES were identified through Psychlit, Medline, Social Sciences Citation Index, and Current Contents. Across studies in similar domains (e.g., studies on multiple personality disorders) combined effect sizes were computed using the Rosenthal-Mullen approach. The DES showed excellent convergent validity with other dissociative experiences questionnaires and interview schedules (combined effect size: d = 1.82; N = 5,916). The DES also showed impressive predictive validity, in particular concerning dissociative disorders (Multiple Personality Disorder: combined effect size d = 1.05; N = l, 705) and traumatic experiences (post-traumatic stress disorder: combined effect size d = 0.75; N = 1,099; and abuse: combined effect size d = 0.52; N = 2,108). However, the discriminant validity was less well established. The DES is sensitive to response and experimenter biases. It is recommended to average DES-scores over more points in time and over more judges. The DES seems to measure the current view on past dissociative experiences. The model of dissociation as a form of autohypnosis failed to receive support from the data. A developmental model to interpret dissociation is proposed.
Ross, C. A., Heber, S., Norton, R. G., Anderson, D., Anderson, G., & Barchet, P. (1989). The dissociative disorders interview schedule: A structured interview. Dissociation, 2(3), 169-189.
Abstract: The Dissociative Disorders Interview Schedule (DDIS), a structured interview, has been developed to make DSM-III diagnoses of the dissociative disorders, somatization disorder, major depressive episode, and borderline personality disorder. Additional items provide information about substance abuse, childhood physical and sexual abuse, and secondary features of multiple personality disorder. These items provide information useful in the differential diagnosis of dissociative disorders. The DDIS has an overall inter-rater reliability of 0.68. For the diagnosis of multiple personality disorder it has a specifity of 100% and a sensitivity of 90%.
Steinberg, M., Hall, P., Lareau, C., & Cicchetti, D. (2001). Recognizing the validity of dissociative symptoms and disorders using the SCID-D-R: Guidelines for clinical and forensic evaluations. Southern California Interdisciplinary Law Journal, 10(2), 225-242.
Abstract: This Article presents guidelines for the systematic evaluation of dissociative symptoms in clinical and forensic cases using the Structured Clinical Interview for DSM-IV Disorders––Revised (SCID-D-R). Since dissociation is a posttraumatic defense which serves as protection from overwhelming trauma, evaluation of dissociative symptoms is particularly relevant to the assessment of the dissociative disorders as well as posttraumatic stress disorder (“PTSD”). The authors review specific SCID-D-R interview criteria that support the accuracy of dissociative diagnosis based on extensive scientific investigations by providing standardized methods that can assist in distinguishing valid versus simulated dissociation. The application of the SCID-D-R in a forensic case is presented to illustrate the utility of this diagnostic tool in the courtroom.
* Welburn, K. R., Fraser, G. A., Jordan, S. A., Cameron, C., Webb, L. M., & Raine, D. (2003). Discriminating dissociative identity disorder from schizophrenia and feigned dissociation on psychological tests and structured Interview. Journal of Trauma & Dissociation, 4(2), 109-130. doi:10.1300/j229v04n02_07
Abstract: Objective: The purpose of this study was to evaluate the relative efficacy of a number of psychological tests and interviews in discriminating dissociative identity disorder (DID) from feigned dissociation and schizophrenia.
Method: Three measures of dissociation (SCID-D, DES, SDQ-5) two personality measures (MMPI-2, Millon-III) and a brief measure of hypnotic susceptibility (Spiegel & Spiegel's Eye-Roll Sign) were assessed for their ability to differentiate these diagnostic groups.
Results: Results indicate that the SCID-D was clearly the most efficacious instrument in discriminating DID from schizophrenia and from feigned dissociation. The DES-Taxon and the SDQ-5 were adequate in screening pathological dissociation from schizophrenia but were less discriminative of feigned dissociation. The commonly used personality inventories were unable to detect feigned dissociation and the DID group tended to have higher elevations on scales measuring psychotic symptoms than did the schizophrenic group. The Eye-Roll Sign discriminated feigned dissociation from those with dissociative disorders.
Conclusions: Structured interviews such as the SCID-D, although resource consuming, are essential in comprehensive assessment of dissociative disorders. Comprehensive assessment of psychotic disorders should include some measure of dissociation.