Ikeda Tatsuya, Urano Yuhei
Graduate School of Education, Hyogo University of Teacher Education, Kobe, Japan.
Faculty of Education, Art and Science, Yamagata University, Yamagata, Japan.
BMC Psychiatry. 2025 Jan 9;25(1):32. doi: 10.1186/s12888-024-06465-w.
The Dissociative Experiences Scale (DES-II) is widely used globally. However, psychometric properties of the scale have not been adequately examined. The present study aimed to examine the psychometric properties and longitudinal stability of the DES-II.
We collected data at two time points, approximately three and a half years apart. At Time 1 (T1), 1029 participants (515 females, 514 males) with a mean age of 44.64 (± 14.02) responded to the survey. Out of the T1 participants, 210 individuals (105 females, 105 males) also responded to the T2 survey. We conducted item parameters of the DES-II with item response theory (IRT).
Our results showed that the DES-II is suitable for measuring strong dissociative traits, with all items displaying high discriminative power. The cut-off points for the DES-II were within a good range of measurement accuracy, and longitudinal stability over approximately three and a half years was adequate.
In the present study, we applied item response theory (IRT) to the DES-II, which has traditionally been interpreted using classical test theory (CTT). Results suggested the need for item-focused assessment rather than relying solely on mean scores or cut-off points. Specifically, results suggested that the severity levels differed across item ratings, and to set cut-off points for each item based on the severity of the ratings. Furthermore, the possibility of cultural differences in response patterns of the DES-II was indicated. However, few studies have discussed cultural differences based on IRT; hence, further research should examine response patterns of the DES-II across various cultures. In conclusion, the DES-II is a valuable tool for assessing dissociative symptoms, with adequate psychometric properties from an item response theory perspective. Clinicians should consider item-specific responses in their assessments, and further research is needed to explore the scale's applicability across diverse populations.
解离体验量表（DES-II）在全球范围内被广泛使用。然而，该量表的心理测量特性尚未得到充分检验。本研究旨在检验DES-II的心理测量特性和纵向稳定性。
我们在两个时间点收集数据，时间间隔约为三年半。在时间1（T1），1029名参与者（515名女性，514名男性）参与了调查，平均年龄为44.64（±14.02）岁。在T1参与者中，有210人（105名女性，105名男性）也参与了T2调查。我们运用项目反应理论（IRT）对DES-II进行了项目参数分析。
我们的结果表明，DES-II适用于测量强烈的解离特质，所有项目都显示出较高的区分度。DES-II的截断点在良好的测量精度范围内，并且在大约三年半的时间里纵向稳定性良好。
在本研究中，我们将项目反应理论（IRT）应用于传统上使用经典测验理论（CTT）进行解释的DES-II。结果表明需要进行以项目为重点的评估，而不是仅仅依赖于平均分或截断点。具体而言，结果表明不同项目评分的严重程度存在差异，应根据评分的严重程度为每个项目设定截断点。此外，研究结果表明DES-II的反应模式可能存在文化差异。然而，很少有研究基于IRT讨论文化差异；因此，未来的研究应考察DES-II在不同文化中的反应模式。总之，从项目反应理论的角度来看，DES-II是评估解离症状的一个有价值的工具，具有足够的心理测量特性。临床医生在评估时应考虑特定项目的反应，并且需要进一步研究来探索该量表在不同人群中的适用性。
