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 Differences between sources

• 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.