Psychometric evaluation of the Hong Kong Chinese version of the Dissociative Experiences Measure, Oxford (HKC-DEMO).

The Dissociative Experiences Measure, Oxford (DEMO) is a recently developed measure that reflects the current conceptualization of dissociation. However, psychometric investigations of the DEMO are still limited. The current study examined the factor structure and psychometric properties of the Hong Kong Chinese version of the DEMO (HKC-DEMO). Online survey data on 914 community-dwelling adults in Hong Kong was extracted from a primary preregistered study on sleep and dissociation. Confirmatory factor analyses revealed that a five-factor structure, identified as "unreality," "numbness and disconnectedness," "memory blanks," "zoned out," and "vivid internal world," fit the data adequately. The five-factor structure fit significantly better than a four-factor structure, which combined "zoned out" and "vivid internal world" as a single factor of "absorption." Furthermore, the HKC-DEMO demonstrated excellent reliability, and satisfactory convergent, and divergent validity. The current study was the first to translate the DEMO to other language and showed that the HKC-DEMO is reliable and valid for use in Hong Kong Chinese adults. Further validation of the HKC-DEMO with a clinical sample and samples with a wider age range would enhance the generalizability of the HKC-DEMO.

Sleep Quality, Sleep-Related Experiences, and Dissociation in Adult Survivors of Childhood Trauma.

OBJECTIVES: Exposure to traumatic stress in childhood increases the risk of sleep disturbances. Preliminary evidence suggests that the relationship between childhood trauma and sleep may depend on trauma chronicity. Additionally, little is known about the relationship between sleep and dissociation, a common symptom in post-traumatic stress disorder. This study examined sleep quality, sleep-related experiences, and dissociation in survivors of childhood trauma with different trauma chronicity. METHOD: Nine-hundred-and-fourteen community-dwelling adults completed an online survey. They were divided into three groups: no childhood trauma, short-term childhood trauma, and chronic childhood trauma. RESULTS: We found that survivors of chronic childhood trauma had poorer sleep quality than survivors of short-term childhood trauma and individuals without a history of childhood trauma, controlling for age, number of trauma types experienced, psychological distress, and PTSD symptoms. The relationship between dissociation and sleep quality was moderated by trauma chronicity such that dissociation was associated with better sleep quality only in the chronic trauma group. Dissociation was positively associated with sleep-related experiences regardless of trauma exposure and trauma chronicity. CONCLUSION: Our findings highlighted the differential impact of acute and chronic traumatic stress on sleep, and suggested that the relationship between dissociation and sleep could depend on trauma chronicity.