The detection and measurement of depersonalization disorder

Depersonalization disorder comprises one of the four major dissociative disorders and yet remains poorly studied. There are no reports describing the application of dissociation scales to this population. Our goal was to investigate the applicability of four such scales to depersonalization disorder and to establish screening criteria for the disorder. Two general dissociation scales and two depersonalization scales were administered to 50 subjects with DSM-III-R depersonalization disorder and 20 healthy control subjects. The depersonalization disorder group scored significantly higher than the normal control group in all scales and subscales. Factor analysis of the Dissociative Experiences Scale (DES) yielded three factors as proposed previously, absorption, amnesia, and depersonalization/derealization. A DES cutoff score of 12, markedly lower than those previously proposed for the screening of other dissociative disorders, is required for the sensitive detection of depersonalization disorder. Alternatively, the DES pathological dissociation taxon (DES-taxon) score recently generated in the literature appears more sensitive to the detection of depersonalization disorder and is better recommended for screening purposes. The other three scales were fairly strongly correlated to the DES, suggesting that they may measure similar but not identical concepts, and cutoff scores are proposed for these scales also. General implications for the screening and quantification of depersonalization pathology are discussed.