Psychometric properties of the 23-Item Clinician Administered Dissociative States Scale (CADSS) in a psychological trauma population.
J Douglas Bremner, David Williamson, Viola Vaccarino
Journal of Affective Disorders November 1, 2024 DOI: 10.1016/j.jad.2024.08.050 (opens in new tab)
Study at a glance
AI-extracted from the abstract| Characteristics | Cross-sectional study Peer reviewed |
|---|---|
| Sample size | 276 |
| Population | Adults with and without posttraumatic stress disorder and a history of psychological trauma, plus healthy controls |
| Topics | Esketamine Ketamine |
| Keywords | Assessment Dissociative disorders Instruments Major depression Nmda receptor antagonists Dissociation depersonalization Derealization Detachment Mental health screening Diagnostic tools Combat trauma Posttraumatic stress |
| Citations | 5 |
| Key findings | The 23-item CADSS demonstrates high internal consistency and valid performance in assessing dissociation in psychologically traumatized participants, with higher scores in those with PTSD. |
Abstract
Dissociative symptoms are both a pathological consequence of exposure to psychological trauma as well as a side effect of N-methyl-d-aspartate (NMDA) receptor antagonist medications; therefore, accurate and valid assessment of these symptoms is important. The psychometric properties of the 23-item Clinician Administered Dissociative States Scale (CADSS) have been characterized in the ketamine and esketamine literatures. Here, we examine its performance in a sample with and without posttraumatic stress disorder (PTSD) and a history of exposure to psychological trauma. Participants with a history of psychological trauma with (N = 148) and without (N = 100) the diagnosis of PTSD and healthy participants without a psychiatric disorder or history of trauma (N = 28) were assessed with the 23-item CADSS and other psychometric and neuropsychological assessments. Analyses were performed to examine internal consistency, convergent and discriminant validity, factor structure, differential performance in populations reported to be more or less likely to report dissociative symptoms (e.g., patients with and without PTSD), and sensitivity to change resulting from exposure to trauma-related sights and sounds. The 23-item CADSS was found to have high internal consistency (Cronbach's alpha 0.91) and a single-factor structure. CADSS total scores in trauma-exposed participants with PTSD were higher than those in trauma-exposed participants without PTSD and non-traumatized non-PTSD participants. Finally, veterans with Iraq combat-related PTSD showed a significant increase in CADSS total score after exposure to combat-related slides and sounds. The 23-item CADSS, already validated as a tool to measure dissociation related to administration of NMDA receptor antagonist medication, performs in a reliable and valid manner in the assessment of dissociation in psychologically traumatized participants.
Comparable studies
Other cross-sectional and survey studies on esketamine, most cited first.
Citations in the library
Cited by 5
- Long-term effectiveness and side-effects of intranasal esketamine in treatment-resistant depression: real-world, single-arm study of over 100 sessions. BJPsych Open January 23, 2026
- The pattern of dissociative symptoms differs between post-traumatic stress disorder and first esketamine administration for treatment-resistant depression. Journal of Affective Disorders June 12, 2025
- Dissociation and Antidepressant Response to Subcutaneous Esketamine: A Clinical Study Journal of Psychiatric Research July 1, 2026
- Development and validation of a short-form (6-item) version of the clinician-administered dissociative states scale (CADSS-SF). European Journal of Psychotraumatology June 15, 2026
- Esketamine hydrochloride in the management of moderate-to-severe depressive symptoms in patients undergoing multiple wound repair surgeries: A multi-centre randomized, double-blind, placebo-controlled trial. Clinical and translational medicine March 1, 2026
Cites 33
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- Efficacy of Esketamine Nasal Spray Plus Oral Antidepressant Treatment for Relapse Prevention in Patients With Treatment-Resistant Depression JAMA Psychiatry June 5, 2019
and 28 more in the library