The gap
A gap in clinical assessment
Dissociative disorders can affect identity, memory, perception, bodily experience, movement, emotions, thoughts, and behaviour. Although the ICD-11 provides a contemporary framework for classifying these disorders, there is currently no brief, standardised screening instrument that comprehensively translates this ICD-11 framework into clinically applicable questions.
The International Dissociative Disorders Questionnaire (IDDQ) is being developed to address this gap. Its aim is to provide clinicians and researchers with a concise, clearly worded, and internationally applicable instrument for identifying the core features of dissociative disorders as defined in the ICD-11.
Grounded in ICD-11
The IDDQ is intended to cover the full range of disorders included in the ICD-11 chapter on dissociative disorders, rather than assessing dissociation only as a single general construct.
Built on international consensus
Experts from different professional, linguistic, and cultural backgrounds evaluate the proposed items across several structured rounds.
Modelled on the ITQ
Like the ITQ, the IDDQ is intended to focus on the essential features of ICD-11 disorders, use clear and accessible language, and apply transparent scoring principles.
Scope
Screening across the ICD-11 chapter on dissociative disorders
Dissociative neurological symptom disorder
6B60
Dissociative amnesia
6B61
Trance disorder
6B62
Possession trance disorder
6B63
Dissociative identity disorder
6B64
Partial dissociative identity disorder
6B65
Depersonalisation-derealisation disorder
6B66
The final structure will depend on the results of the Delphi study and subsequent psychometric validation.
Development programme
Where the project stands
Item pool development
Delphi study
Current stage
Pilot testing
Psychometric validation
Translation & cultural adaptation
The IDDQ is currently under development and is not yet available as a validated clinical instrument.
Get involved
The next stage of the project is an international Delphi study. Experts from different professional, linguistic, and cultural backgrounds will be invited to evaluate the proposed items across several structured rounds. The aim is to identify the questions that are most clinically relevant, clearly formulated, diagnostically specific, and suitable for international use.
Join the Delphi study
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