The Detection of Invalid Responses Using the Dissociative Experiences Scale-V (DES-V).

The Dissociative Experiences Scale (DES) is the most widely used self-report measure of dissociation but lacks a validity scale. Abu-Rus et al. (2020) created the DES-V by embedding atypical and inconsistency items in the DES, ultimately concluding that atypicality demonstrated the greatest ability to differentiate honest respondents from feigners. Among their study limitations, Abu-Rus et al. noted the homogeneous nature of their clinical group (i.e., largely comprising individuals with PTSD) and the potential need to refine the existing atypicality items for a more heterogenous dissociation population. The current study aimed to refine the DES-V by enlisting dissociation experts to improve the believability of the atypical items (while simultaneously ensuring they did not betoken any actual dissociative symptomology) and by supplementing the online sample with a clinical sample that included a broad range of dissociative disorders. Data cleaning comprised eight different techniques, to better ensure the validity of the online sample. Honest and Feigning groups completed the assessments through Amazon's Mechanical Turk; the clinical dissociative disorder group completed hard copy versions. The atypicality scale discriminated the three groups well, with the Feigning group scoring significantly higher than both of the honest groups (online and clinical). The mean atypicality scores of the two honest groups did not differ significantly. In addition, the scale incremented over the original DES-V in a logistic regression predicting honest and feigning participants. These robust results suggest that the revised DES-V could provide researchers with a valuable tool for validating online samples with greater precision - an increasingly vital need in light of the growing reliance on online samples.