The prevalence and biometric structure of pathological dissociation in the general population: Taxometric and behavior genetic findings.

Abstract

Taxometric and biometric analyses were conducted on 2 North American samples to investigate the prevalence and biometric structure of pathological dissociation. Results indicated that approximately 3.3% of the general population belongs to a pathological dissociative taxon. A brief 8-item self-report scale called the DES-T can be used to calculate taxon membership probabilities in clinical and nonclinical samples of adults (a SAS scoring program is provided for this purpose). The genetic and environmental architecture of pathological dissociative symptoms was explored by conducting a biometric analysis on DES-T ratings from 280 identical and 148 fraternal twins. The findings suggest that approximately 45% of the observed variance on the DES-T can be attributed to shared environmental influences. The remaining variance is due to nonshared environmental influences.

Taxometric Investigation of PTSD: Data From Two Nationally Representative Samples

“…Specifically, several types of psychopathology, particularly those that are associated with strong biological or environmental influences, have been found to be taxonic. For example, discrete categories have been indicated with regard to schizotypy ( [Korfine and Lenzenweger, 1995] and [Lenzenweger and Korfine, 1992] ), bulimia nervosa (Gleaves et al, 2000), endogenous depression (Haslam & Beck, 1994), and pathological dissociation ( [Waller et al, 1996] and [Waller and Ross, 1997] ). Thus, any attempts to refine psychiatric nosology should not be based on preconceived, or even "expert," notions regarding the categorical or dimensional nature of psychopathology.…”

Dissociative tendencies and individual differences in high hypnotic suggestibility

“…Individuals falling into the taxon are argued to experience, or have a heightened predisposition to, dissociative psychopathology. Average DES scores, DES-T scores, and the Bayesian probability of membership in the taxon (Waller & Ross, 1997) were computed. We used a categorical probability cut-o↵ of .5 (e.g., Watson, 2003) for nominal inclusion in the taxon.…”

Investigating the construct validity of the dissociative taxon: Stability analyses of normal and pathological dissociation.

“…We used the standard response format for the DES (see Carlson & Putnam, 1992), in which ratings are made on an 11-point scale (0%, 10%, 20%, etc. ); it should be noted that Waller and Ross (1997) employed a modified 21-point scale (0%, 5%, 10%, etc.) in their study.…”

“…Carlson and Putnam (1992) state that "the DES was designed as a trait measure of dissociation…We expect, then, stable scores over shorter periods of time…" (p. 3) Second, a prominent contemporary model of dissociative pathology emphasizes the etiological role of childhood traumas (e.g., Waller et al, 1996;Waller & Ross, 1997; for a dissenting view, however, see Lilienfeld et al, 1999). Waller and Ross (1997), for example, note that "a dominant model in the dissociation literature posits that dissociative pathology stems from traumatic childhood events (such as sexual, physical, or extreme emotional abuse) that occur frequently within the home" (p. 507). They provided suggestive support for this model by establishing that approximately 45% of the variance Investigating the Construct Validity 6 in DES-T scores could be attributed to shared environmental influences.…”

“…Investigating the Construct Validity 5 Waller and Ross (1997) further investigated the DES-T items in a very large community sample and again found evidence of a pathological dissociative taxon. In addition, they created a scoring program that calculates precise Bayesian taxon membership probabilities (ranging from 0 to 1.00) for each respondent (this program is presented in an appendix; see Waller & Ross, 1997, p. 510).…”