ICD-116B65	PARTIAL DISSOCIATIVE IDENTITY DISORDER Partial dissociative identity disorder
ICD-10F44.8	Other dissociative [conversion] disorders
DSM-5-TRF44.89	Other Specified Dissociative Disorder

1. Definition and nosology

Partial Dissociative Identity Disorder (ICD-11: 6B65 Partial Dissociative Identity Disorder) — similar to DID (6B64), but differs in that non-dominant identities do not consistently fully occupy the patient's behaviour or conscious function. Instead, non-dominant identities interfere, but do not fully seize “executive control.”

In ICD-11, added for the first time as an official diagnostic category; not separate in DSM-5-TR (in DSM-5-TR can be assessed under Other Specified Dissociative Disorder).

2. History

• ICD-11 (2019) — recognition as part of the DID spectrum, with the partial form as an official category.
• New diagnostic framework for conditions recognized in clinical practice as ‘DDNOS’ or ‘DID-NOS’.

3. Epidemiology

• Prevalence, precise data limited — believed to be more common than DID.
• Develops on trauma basis.
• Comorbidity resembling DID.

4. Aetiology and pathogenesis

Same as DID — severe childhood trauma, disorganized attachment, neurobiological dissociative processes.

5. Clinical features

• Two or more distinct identity states.
• Non-dominant identities intrude — internal voices, thoughts, feelings, actions – but do not fully occupy patient's behavior and consciousness.
• Dominant identity controls daily functioning.
• Less amnesia compared to DID.
• Distress and functional impairment.

6. Diagnosis

6.1 Unified diagnostic criteria (ICD-11)

A. Two or more distinct identity states.

B. Non-dominant identities do not consistently take full control; of the consciousness and behaviour of the dominant identity; but are present as an intrusive experience.

C. Significant distress or functional impairment.

D. Exclusion of substance or medical condition.

6.2 Source-specific clarifications

• ICD-11 — differs from DID by ‘not fully capturing.’
• DSM-5-TR — may be assessed within Other Specified Dissociative Disorder (F44.89).

6.3 Diagnostic algorithm

Same as DID (see 6B64 §6.3).

6.4 Differential diagnosis

7. Examination and assessment

Same as DID (SCID-D-R, DES, MID).

8. Treatment

The phase-oriented approach is adapted for DID (ISSTD 2011). For treatment principles, phases, and specific methodologies, see section 6B64 “Treatment” (including “Treatment methods”).

9. Prognosis

Functional recovery with phase-oriented therapy; similar to DID.

10. Myths and misconceptions

Myth 1: “Partial DID is a ‘mild form’ of DID”

Evidence: distinct diagnostic category; functional impairment and trauma burden may be comparable to DID.

Myth 2: “Internal voices are always a psychotic symptom”

Evidence: dissociative voices differ from psychotic symptoms — internal dialogue, ‘own’ feeling, weak response to antipsychotics; SCID-D-R for differentiation.

Myth 3: “Antipsychotic ‘cures’ voices in partial DID”

Evidence: dissociative voices do not respond to antipsychotics; psychotherapy first-line.

Myth 4: “The patient is ‘role-playing’”

Evidence: Different from factitious disorder (6D50) — no motivation for gain; clinical experience is distressing for the patient.

11. Sources

1. WHO. ICD-11. 6B65 Partial dissociative identity disorder. 2024.
2. APA. DSM-5-TR. 2022.
3. ISSTD. Guidelines for Treating Dissociative Identity Disorder in Adults, Third Revision. J Trauma Dissociation 2011;12(2):115–187.
4. Reinders A.A.T.S. et al. J Nerv Ment Dis 2016;204(6):445–457.