Dissociative identity disorder (DID) is defined in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) as an identity disruption indicated by the presence of two or more distinct personality states (experienced as possession in some cultures), with discontinuity in the sense of self and agency, and with variations in affect, behavior, consciousness, memory, perception, cognition, or sensory-motor functioning. Individuals with DID experience recurrent gaps in autobiographical memory. The signs and symptoms of DID may be observed by others or reported by the individual. DSM-5 stipulates that symptoms cause significant distress and are not attributable to accepted cultural or religious practices. Conditions similar to DID but with less-than-marked symptoms (e.g., subthreshold DID) are classified among “other specified dissociative disorders.”
DID is a complex, posttraumatic developmental disorder. DSM-5 specifically locates the dissociative disorders chapter after the chapter on trauma- and stressor-related disorders, thereby acknowledging the relationship of the dissociative disorders to psychological trauma. The core features of DID are usually accompanied by a mixture of psychiatric symptoms that, rather than dissociative symptoms, are typically the patient’s presenting complaint. As is common among individuals with complex, posttraumatic developmental disorders, DID patients may suffer from symptoms associated with mood, anxiety, personality, eating, functional somatic, and substance use disorders, as well as psychosis, among others. DID can be overlooked due to both this polysymptomatic profile and patients’ tendency to be ashamed and avoidant about revealing their dissociative symptoms and history of childhood trauma (the latter of which is strongly implicated in the aetiology of DID).
Multiple personality states have been described by renowned theorists, including Pierre Janet, Sigmund Freud, Alfred Binet, William James, Benjamin Rush, Morton Prince, Boris Sidis, Enrico Morselli, and Sandor Ferenczi. The first published cases are those of Jeanne Fery, reported in 1586, and a case of “exchanged personality” that dates to Eberhardt Gmelin’s account of 1791. Many of the individuals considered hysterics in the nineteenth century would today be diagnosed with dissociative disorders. Early debates focused upon whether hysteria should be conceptualised as a somatoform condition, a condition of altered states of consciousness, or a condition rooted entirely in suggestion.
Current debates about the validity and aetiology of DID echo early debates about hysteria and also other trauma-based phenomena such as dissociative amnesia. Historically, trauma has stirred debate within and outside the mental health field; periods of interest in trauma have been followed by disinterest and disavowal of its prevalence and impact. The previous lack of systematic evidence about the relationship between trauma and clinical symptomatology contributed to misconceptions about trauma-related problems (such as attributing these symptoms to psychosis). The absence of systematic documentation of the extent of child abuse further inhibited efforts to identify and define the complex syndromes that were closely associated with it.
Additionally, a broadening of the range of conditions subsumed by a diagnosis of schizophrenia moved the etiological focus from trauma and dissociation to a variant of genetic illness/brain pathology. Rosenbaum documented that as the concept of schizophrenia began to gain ascendancy among clinicians, the concept of DID markedly decreased—a change that likely occurred because schizophrenia and DID have some similar symptoms. Early writers on psychoses/schizophrenia (e.g., Kahlbaum, Kraepelin, Bleuler, Meyer, Jung, Schneider, and Bateson) reference cases of “psychosis” that closely resemble, or are seemingly typical of, DID. Bleuler references many such cases, including some in which “the ‘other’ personality is marked by the use of different speech and voice … Thus we have here two different personalities operating side by side, each one fully attentive. However, they are probably never completely separated from each other since one may communicate with both.”
Social, scientific, and political influences have since converged to facilitate increased awareness of dissociation. These diverse influences include the resurgence of recognition of the impact of traumatic experiences, feminist documentation of the effects of incest and violence toward women and children, continued scientific interest in the effects of combat, and the increasing adoption of psychotherapy into medicine and psychiatry. The increased awareness of trauma and dissociation led to the inclusion in DSM-III of posttraumatic stress disorder (PTSD), dissociative disorders (with DID referred to as multiple personality disorder), and somatoform disorders, and to the discarding of hysteria. Concurrently, traumatised and dissociative patients with severe symptoms (e.g., suicidality, impulsivity, self-mutilation) gained greater attention as psychiatry began to treat more severe psychiatric conditions with psychotherapy, and as some acutely destabilised DID patients required psychiatric hospitalisation. These developments facilitated a climate in which researchers and clinicians could consider how a traumatised child or adult might psychologically defend himself or herself against abuse, betrayal, and violence. Additionally, the concepts of identity, alongside identity crisis, identity confusion, and identity disorder, were introduced to psychiatry and psychology, thereby emphasising the links between childhood, society, and epigenetic development.
In this climate of renewed receptivity to the study of trauma and its impact, research in dissociation and DID has expanded rapidly in the 40 years spanning 1975 to 2015. Researchers have found dissociation and dissociative disorders around the world. For example, in a sample of 25,018 individuals from 16 countries, 14.4% of the individuals with PTSD showed high levels of dissociative symptoms. This research led to the inclusion of a dissociative subtype of PTSD in DSM-5. Recent reviews indicate an expanding and important evidence base for this subtype.
Notwithstanding the upsurge in authoritative research on DID, several notions have been repeatedly circulated about this disorder that is inconsistent with the accumulated findings on it. We argue here that these notions are misconceptions or myths. We have chosen to limit our focus to examining myths about DID, rather than dissociative disorders or dissociation in general. Careful reviews about broader issues related to dissociation and DID have recently been published. The purpose of this article is to examine some misconceptions about DID in the context of the considerable empirical literature that has developed about this disorder. We will examine the following notions, which we will show are myths:
- a belief that DID is a “fad”
- a belief that DID is primarily diagnosed in North America by DID experts who overdiagnose the disorder
- a belief that DID is rare
- a belief that DID is an iatrogenic disorder rather than a trauma-based disorder
- a belief that DID is the same entity as a borderline personality disorder
- a belief that DID treatment is harmful to patients
MYTH 1: DID IS A FAD
Some authors opine that DID is a “fad that has died. A “fad” is widely understood to describe “something (such as an interest or fashion) that is very popular for a short time. As we noted above, DID cases have been described in the literature for hundreds of years. Since the 1980 publication of DSM-III, DID has been described, accepted, and included in four different editions of the DSM. Formal recognition as a disorder for over three decades contradicts the notion of DID as a fad.
To determine whether research about DID has declined (which would possibly support the suggestion that the diagnosis is a dying fad), we searched PsycInfo and MEDLINE using the terms “multiple personality disorder” or “dissociative identity disorder” in the title for the period 2000–14. Our search yielded 1339 hits for the 15 years. This high number of publications speaks to the level of professional interest that DID continues to attract.
Recent reviews attest that a solid and growing evidence base for DID exists across a range of research areas:
- DID patients can be reliably and validly diagnosed with structured and semi-structured interviews, including the Structured Clinical Interview for Dissociative Disorders-Revised (SCID-D-R) and Dissociative Disorders Interview Schedule (DDIS) (reviewed in Dorahy et al. ). DID can also be diagnosed in clinical settings, where structured interviews may not be available or practical to use.
- DID patients are consistently identified in outpatient, inpatient, and community samples around the world.
- DID patients can be differentiated from other psychiatric patients, healthy controls, and DID simulators in neurophysiological and psychological research.
- DID patients usually benefit from psychotherapy that addresses trauma and dissociation by expert consensus guidelines.
An expanding body of research examines the neurobiology, phenomenology, prevalence, assessment, personality structure, cognitive patterns, and treatment of DID. This research provides evidence of DID’s content, criterion, and construct validity. The claim that DID is a “fad that has died” is not supported by an examination of the body of research about this disorder.
MYTH 2: DID IS PRIMARILY DIAGNOSED IN NORTH AMERICA BY DID EXPERTS WHO OVER-DIAGNOSE THE DISORDER
Some authors contend that DID is primarily a North American phenomenon, that it is diagnosed almost entirely by DID experts, and that it is over-diagnosed. Paris opines that “most clinical and research reports about this clinical picture [i.e., DID] have come from a small number of centres, mostly in the United States that specialise in dissociative disorders.” As we show below, the empirical literature indicates not only that DID diagnose around the world and by clinicians with varying degrees of experience with the disorder, but that DID is underdiagnosed rather than over-diagnosed.
Belief That DID Is Primarily Diagnosed in North America
According to some authors, DID is primarily diagnosed in North America. We investigated this notion in three ways: by examining the countries in which prevalence studies of DID have been conducted; by inspecting the countries from which DID participants were recruited in an international treatment-outcome study of DID; and by conducting a systematic search of published research to determine the countries where DID has been most studied.
First, our results show that DID is found in prevalence studies around the world whenever researchers conduct systematic assessments using validated interviews. Fourteen studies that have utilised structured or semi-structured diagnostic interviews for dissociative disorders to assess the prevalence of DID have been conducted in seven countries: Canada, Germany, Israel, the Netherlands, Switzerland, Turkey, and the United States.
Second, in addition to the prevalence studies, a recent prospective study assessed the treatment outcome of 232 DID patients from around the world. The participants lived in Argentina, Australia, Belgium, Brazil, Canada, Germany, Israel, the Netherlands, New Zealand, Norway, Singapore, Slovakia, South Africa, Sweden, Taiwan, and the United States. That is, the participants came from every continent except Antarctica.
Third, we conducted a systematic search of published, peer-reviewed DID studies. Using the search terms “dissociative identity disorder” and “multiple personality disorder,” we conducted a literature review for the period 2005–13 via MEDLINE, PsycINFO, and the Journal of Trauma and Dissociation. This search yielded 340 articles. We selected empirical research studies in which DID or multiple personality disorder had been diagnosed in patients. We recorded the authors’ countries and institutions, and whether structured interviews were used to diagnose DID. Over this nine-year period, 70 studies included DID patients. Significantly, these studies were conducted by authors from 48 institutions in 16 countries. In 28 (40%) of studies, structured interviews (SCID-D or DDIS) were administered to diagnose DID.
In summary, all three methods contradicted the claim that DID is diagnosed primarily in North America.
Belief That DID Is Primarily Diagnosed by DID experts
Lynn and colleagues argue that “most DID diagnoses derive from a small number of therapy specialists in DID.” Other critics voice similar concerns. Research does not substantiate this claim. For example, 292 therapists participated in the prospective treatment-outcome study of DID conducted by Brand and colleagues. The majority of therapists were not DID experts.
Similarly, a national random sample of experienced U.S. clinicians found that 11% of patients treated in the community for borderline personality disorder (BPD) also met criteria for comorbid DID. None of the therapists was DID experts. In an Australian study of 250 clinicians from several mental health disciplines, 52% had diagnosed a patient with DID. These studies show that DID is diagnosed by clinicians around the world with varying degrees of expertise in DID.
Belief That DID Is Over-diagnosed
A related myth is that DID is over-diagnosed. Studies show, however, that most individuals who meet criteria for DID have been treated in the mental health system for 6–12 years before they are correctly diagnosed with DID. Studies conducted in Australia, China, and Turkey have found that DID patients are commonly misdiagnosed. For example, in a study of consecutive admissions to an outpatient university clinic in Turkey, 2.0% of 150 patients were diagnosed with DID using structured interviews confirmed by clinical interview. Although 12.0% were assessed to have one of the dissociative disorders, only 5% of the dissociative patients had been diagnosed previously with any dissociative disorder. Likewise, although 29% of the patients from an urban U.S. hospital-based, outpatient psychiatric clinic were diagnosed via structured interviews with dissociative disorders, only 5% had a diagnosis of dissociative disorders in their medical records. Similar results have been found in consecutive admissions to a Swiss university outpatient clinic and consecutive admissions to a state psychiatric hospital in the United States when patients were systematically assessed with structured diagnostic interviews for dissociative disorders. This pattern is also found in nonclinical samples. Although 18.3% of women in a representative community sample in Turkey met criteria for having a dissociative disorder at some point in their lives, only one-third of the dissociative disorders group had received any type of psychiatric treatment. The authors concluded, “The majority of dissociative disorders cases in the community remain unrecognised and unserved.”
Studies that examine dissociative disorders in general, rather than focusing on DID, find that this group of patients are often not treated despite high symptomatology and poor functioning. A random sample of adolescents and young adults in the Netherlands showed that youth with dissociative disorders had the highest level of functional impairment of any disorder studied but the lowest rates (2.3%) of referral for mental health treatment. Those with dissociative disorders in a nationally representative sample of German adolescents and young adults were highly impaired, yet only 16% had sought psychiatric treatment. These findings point to the conclusion that dissociative disorder patients are underrecognized and undertreated, rather than being over-diagnosed.
Why is DID so often underdiagnosed and undertreated? Lack of training, coupled with scepticism about dissociative disorders seems to contribute to the under-recognition and delayed diagnosis. Only 5% of Puerto Rican psychologists surveyed reported being knowledgeable about DID, and the majority (73%) had received little or no training about DID. Clinicians’ scepticism, about DID, increased as their knowledge about it decreased. Among U.S. clinicians who reviewed a vignette of an individual presenting with the symptoms of DID, only 60.4% of the clinicians accurately diagnosed DID. Clinicians misdiagnosed the patient as most frequently suffering from PTSD (14.3%), followed by schizophrenia (9.9%) and major depression (6.6%). Significantly, the age, professional degree, and years of experience of the clinician were not associated with an accurate diagnosis. Accurate diagnoses were most often made by clinicians who had previously treated a DID patient and who were not sceptical about the disorder. It concerns that clinicians were equally confident in their diagnoses, regardless of their accuracy. A study in Northern Ireland found a similar link between a lack of training about DID and misdiagnosis by clinicians. Psychologists more accurately detected DID than did psychiatrists (41% vs 7%, respectively). Australian researchers found that misdiagnosis was often associated with lack of training about DID and with scepticism regarding the diagnosis. They concluded, “Clinician scepticism may be a major factor in under-diagnosis as diagnosis requires [dissociative disorders] first being considered in the differential. Displays of scepticism by clinicians, by discouraging openness in patients, already embarrassed by their symptoms, may also contribute to the problem.”
In short, far from being over-diagnosed, studies consistently document that DID is underrecognized. When systematic research is conducted, DID is found around the world by both experts and nonexperts. Ignorance and scepticism about the disorder seem to contribute to DID being an underrecognized disorder.
MYTH 3: DID IS RARE
Many authors, including those of psychology textbooks, argue that DID is rare. The prevalence rates found in psychiatric inpatients, psychiatric outpatients, the general population, and a specialised inpatient unit for substance dependence suggest otherwise. DID is found in approximately 1.1%–1.5% of representative community samples. Specifically, in a representative sample of 658 individuals from New York State, 1.5% met criteria for DID when assessed with SCID-D questions. Similarly, a large study of community women in Turkey (n = 628) found 1.1% of the women had DID.
Studies using a rigorous methodology, including consecutive clinical admissions and structured clinical interviews, find DID in 0.4%–6.0% of clinical samples. Studies assessing groups with particularly high exposure to trauma or cultural oppression show the highest rates. For example, 6% of consecutive admissions in a highly traumatised, U.S. inner city sample were diagnosed with DID using the DDIS. By contrast, only 2.0% of consecutive psychiatric inpatients received a diagnosis of DID via the SCID-D in the Netherlands. The difference in prevalence may partially stem from the very high rates of trauma exposure and oppression in the U.S. inner-city, primarily minority sample.
Possession states are a cultural variation of DID that has been found in Asian countries, including China, India, Iran, Singapore, and Turkey, and also elsewhere, including Puerto Rico and Uganda. For example, in a general population sample of Turkish women, 2.1% of the participants reported an experience of possession. Two of the 13 women who reported an experience of possession had DID when assessed with the DDIS. Western fundamentalist groups have also characterised DID individuals as possessed. Such findings are inconsistent with the claim that DID is rare.
To Be Continued Here: