ICD-116B64	DISSOCIATIVE IDENTITY DISORDER (DID) Dissociative identity disorder
ICD-10F44.81	Dissociative identity disorder
DSM-5-TRF44.81	Dissociative Identity Disorder

1. Definition and nosology

Dissociative Identity Disorder (DID; ICD-11: 6B64 Dissociative Identity Disorder; DSM-5-TR: F44.81) — a severe dissociative disorder characterized by transitions between two or more distinct personality states (“identities”, “alters”). Each identity has a relatively enduring sense of self, memory, behavior, affect, perception, and cognition patterns. Concurrently, persistent dissociative amnesias (for daily events, important personal information, trauma).

DID — associated with severe childhood trauma (especially repeated physical or sexual abuse); the “split personality” image distorted in mass media differs from clinical reality.

2. History

• 1791 — Eberhardt Gmelin first case description.
• Janet P. (1880s) — concept of ‘dissociation’.
• DSM-III (1980) — “Multiple Personality Disorder”.
• DSM-IV (1994) — Term ‘Dissociative Identity Disorder’.
• 1980s–1990s — ‘False Memory’ controversy; allegations of ‘iatrogenic induction’ in some diagnostic cases.
• ISSTD Treatment Guidelines (Adult Treatment, 3rd Revision 2011) — standardized the phase-oriented approach.

3. Epidemiology

• Prevalence in clinical populations: 1–3%; in general population ~1.5% (Sar V. ISRN Psychiatry 2011 review).
• Sex: 5–9 times higher in females in clinical populations.
• Onset: symptoms develop in childhood, clinical presentation often at 20–40 years.
• Comorbidity: MDD, PTSD, complex PTSD, BPD, somatic symptom, eating disorders, substance use, very high suicide risk.

4. Aetiology and pathogenesis

• Trauma model — repeated severe childhood trauma (sexual or physical violence, neglect, caregiver violence); 90%+ of patients show trauma history (Putnam F.W. reviews).
• Neurobiological — hippocampal and amygdala volume reduction; default mode and salience network dysregulation (Reinders A.A. et al. reviews).
• Attachment — disorganized attachment style in childhood.
• Iatrogenesis / supporters of the social-cognitive model — some diagnoses may be the result of therapeutic induction (critique by Lilienfeld S.O.); however, most research supports the trauma-based model.

5. Clinical features

• Two or more distinct identity states — some patients document overt transitions, others appear only with “internal voices,” sense of “loss of control.”
• Persistent amnesias — daily events, personal information, traumatic episodes.
• Depersonalization and derealization.
• Identity transitions as a response to stress, triggers.
• Self-harm, suicidal attempts, somatic symptoms.
• Complex dissociative symptoms (dissociative seizures, somatoform).

6. Diagnosis

6.1 Unified diagnostic criteria

A. Two or more distinct personality states — significant discontinuity in sense of self and agency, alterations in behavior, affect, perception, cognition, or sensorimotor function.

B. Recurrent amnesias regarding daily events, important personal information, and/or traumatic events.

C. Significant distress or functional impairment.

D. Not part of a widespread cultural or religious practice.

E. Exclusion of substance or medical condition (e.g., seizure).

6.2 Source-specific clarifications

• DSM-5-TR — same criteria; imaginary companion in children excluded as part of normal development.
• ICD-11 — amnesia is not required: it says “there are typically episodes of amnesia”, whereas DSM-5-TR requires it as criterion B. Trance and possession disorders are separate ICD-11 categories (6B62, 6B63).
• ISSTD Guidelines 2011 — the diagnosis must be confirmed by a structured interview (SCID-D).

6.3 Diagnostic algorithm

1. Clinical interview — trauma history, dissociative symptoms.
2. SCID-D (Structured Clinical Interview for DSM Dissociative Disorders) is the gold standard.
3. Scale — DES (Dissociative Experiences Scale, ≥30 cut-off, ≥45 DID indicator); MID (Multidimensional Inventory of Dissociation).
4. Comorbidity (PTSD, BPD, MDD, substance).
5. Suicide and self-harm risk (high).
6. Medical and neurological – seizures, encephalitis excluded (EEG, MRI).

6.4 Differential diagnosis

7. Examination and assessment

• SCID-D-R is the gold-standard structured interview.
• DES, MID scales.
• C-SSRS suicide; self-harm assessment.
• EEG rule out seizure.

8. Treatment

8.1 General principles (ISSTD 2011)

1. Phase-oriented (three-phase) approach:
   • Phase 1 — stabilization and symptom reduction: safety, emotion regulation, coping skills, hospitalization reduction, self-harm management.
   • Phase 2 — processing of traumatic memories: adapted trauma-focused intervention.
   • Phase 3 — integration and rehabilitation: inter-identity communication, functional restoration, relationships.
2. Specific psychotherapeutic approaches — excerpt from Internal Family Systems (Schwartz R.), modified EMDR.
3. Pharmacotherapy — no specific approval for DID; SSRIs, prazosin (for nightmares) for comorbid PTSD, MDD, anxiety symptoms.
4. Hospitalize — in acute self-harm or suicide risk.
5. Multidisciplinary approach — psychiatrist, psychologist, social support.
6. Long-term treatment (years); clinician continuity and therapeutic alliance are critical.

8.2 Source-specific clarifications

• ISSTD 2011 — phase-oriented gold standard.
• Trauma-based approach and iatrogenesis caution — avoid searching or inducing ‘alters’.

Treatment methods

1. Phase-Oriented Treatment (ISSTD) — Three-phase approach; sequence and patient stability are fundamental.
2. Structured Clinical Interview for DSM Dissociative Disorders, Revised (SCID-D-R) — 277-item structured interview; gold standard.
3. Dissociative Experiences Scale (DES) — 28 items; screening.
4. Multidimensional Inventory of Dissociation (MID) — 218 items; detailed dissociative profile.
5. EMDR — modified — Trauma processing after stabilization; sequential and adapted to patient's pace.

9. Prognosis

• Functional recovery with long-term phase-oriented therapy.
• High suicide and self-harm risk monitored.
• Comorbidity treatment is important.

10. Myths and misconceptions

Myth 1: “DID is ‘split personality’ as in mass media”

Evidence: Film or television portrayals (dramatic transitions, “different people” do not coincide with the more subtle clinical picture in many patients — more “loss of control”, internal voices, amnesias are dominant).

Myth 2: “DID is a false condition induced by the therapist”

Evidence: strong association with childhood trauma (Putnam reviews); neurobiological markers (Reinders fMRI); international research consistent. However, diagnosis should be cautious — avoiding induction techniques for alters is important.

Myth 3: “DID is a rare or fabricated disorder”

Evidence: Clinical prevalence in populations 1–3% (Sar 2011); an underdiagnosed condition.

Myth 4: “Hypnosis or hospitalization is the main treatment”

Evidence: Phase-oriented psychotherapy is first-line; hypnosis can be used as an adjunct (with caution); inpatient admission only in acute self-harm or suicide risk.

Myth 5: “A patient with DID is prone to committing violence”

Evidence: Patients with DID are more likely to be victims of violence; violence towards others is rare. Parallel to myth ‘people with schizophrenia are dangerous.’

Myth 6: “The main goal is to ‘merge all identities into one’”

Evidence: integration typical goal, but complete assimilation not achievable in all patients; “cooperation” and “functional activity” also accepted as clinical outcomes.

11. Sources

1. WHO. ICD-11. 6B64 Dissociative identity disorder. 2024.
2. APA. DSM-5-TR. 2022.
3. International Society for the Study of Trauma and Dissociation. Guidelines for Treating Dissociative Identity Disorder in Adults, Third Revision. J Trauma Dissociation 2011;12(2):115–187.
4. Sar V. Epidemiology of dissociative disorders: an overview. Epidemiology Research International 2011;2011:404538.
5. Putnam F.W. Diagnosis and Treatment of Multiple Personality Disorder. Guilford Press; 1989.
6. Reinders A.A.T.S. et al. The psychobiology of authentic and simulated dissociative personality states: the full Monty. J Nerv Ment Dis 2016;204(6):445–457.
7. Steinberg M. Structured Clinical Interview for DSM-IV Dissociative Disorders, Revised (SCID-D-R). APA Press; 1994.
8. Lilienfeld S.O., Lynn S.J., Kirsch I. et al. Dissociative identity disorder and the sociocognitive model: recalling the lessons of the past. Psychol Bull 1999;125(5):507–523.
9. Schwartz R.C., Sweezy M. Internal Family Systems Therapy. 2nd ed. New York: Guilford Press, 2020.