The Psychopathology and Assessment of DID
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The Overlap of DID With Other Conditions
In his evaluation of the literature concerning the psychopathology of individuals with DID, Gleaves (1996) made the same error he accused Spanos of having made in the case of multiple identity enactments and DID: equating one diagnostic feature with one disorder. Specifically, Gleaves equated attention seeking with histrionic personality disorder (HPD) and argued that because the SCM posits that gaining attention is an important motivation for DID patients, this model predicts that these patients should exhibit higher rates of HPD than other patients (see also Dell, 1998). Gleaves's review of the literature indicated, however, that DID patients do not exhibit markedly elevated rates of HPD.
Nevertheless, attention seeking is only one characteristic of HPD and is found in a number of conditions other than HPD. Moreover, Spanos (1994) never used the terms histrionic personality disorder or hysteria in his review, and his description of the modal DID patient as exhibiting "mood swings, shameful or unrepresentative behaviors, ambivalent feelings, hostile fantasies, forgetfulness, guilt-inducing sexual fantasies, and bad habits" (p. 155) does not appear prototypal of patients with HPD. As a consequence, it is not clear that the data presented by G1eaves (1996, pp. 44-45) regarding the relatively low rates of HPD among DID patients are directly relevant to the SCM or to Spanos's (1994) exposition of it. [*2]
Although Gleaves (1996) reviewed evidence from studies by Ellason, Ross, and Fuchs (1996) and Lauer, Black, and Keen (1993) indicating that many DID patients meet criteria for avoidant personality disorder (APD) and are thus presumably unlikely to be strongly motivated by a need for attention, the findings of these two studies are difficult to interpret. The study by Ellason et al. did not include either a psychiatric or normal comparison group, and the study by Lauer et al. reported no significant differences in the rates of APD between small samples of DID patients (N = 14) and BPD patients (N = 13). [*3]
Moreover, the finding that DID co-varies with APD, if demonstrated in studies with appropriate comparison groups, does not contradict the SCM.
DSM-IV (APA, 1994) noted that individuals with APD "desire affection and acceptance and may fantasize about idealized relationships with others" (p. 663) and are characterized by "a need for reassurance" (p. 664). In addition, individuals with APD tend to be overly dependent on others for approval (Troll, Widiger, & Frances, 1987). Thus, APD is associated with several traits that would be expected to increase the seeking of approval from authority figures and perhaps foster receptivity to therapist suggestions.
Furthermore. many of the clinical features Gleaves (1996) described may be associated with BPD, which Gleaves largely ignored in his review. BPD, like HPD, is characterized by attention
seeking (APA, 1994, p. 657). In addition, BPD has been found to co-occur extensively with DID. Across a number of studies
the proportion of DID patients fulfilling diagnostic criteria for BPD has ranged from 35% to 71 %. Although several of these studies lacked comparison groups (and the study by Lauer et al., 1993, included only a comparison group of BPD patients), the study by Scroppo et al. ( 1998) found statistically significant and large (Cohen ' s d = 1.52) differences in the rates of BPD between DID patients and non-dissociative psychiatric patients. In addition, Yargic et al. ( 1998) reported significantly higher rates of BPD among a group of DID patients than among three groups of patients with schizophrenia, panic disorder, and partial complex seizure disorder, respectively, and Dell (1998) reported significantly higher rates of BPD among DID patients than among patients with a diagnosis of dissociative disorder not otherwise specified.
Gleaves ( 1996) sidestepped the issue of the extensive overlap between DID and BPD by stating that "to thoroughly discuss the connection between borderline personality disorder and DID would be beyond the scope of this article" (p. 44) and noting that the overlap between these two conditions is not surprising given their association with child abuse and PTSD. Nevertheless, Gleaves did not address the possibility that both the history of abuse and PTSD symptoms may be seized upon as evidence of potential DID by therapists who seek to explain many of the puzzling features of BPD, such as identity disturbance, dramatic changes in mood, and marked instability in interpersonal relationships, in terms of DID (Ganaway, 1995; see Piper, 1997, for a discussion of the potential "elasticity" of the DID diagnostic criteria in the hands of some clinicians). Because a number of the signs and symptoms of BPD resemble those of DID, the possibility that these two conditions are readily confused with one another merits systematic examination in studies of diagnosticians' judgments.
The Assessment and Diagnosis of DID
Gleaves (1996) reviewed a large body of evidence indicating that the diagnosis of DID can be made reliably and validly using self-report and structured interview measures. It is unclear, however, how this literature is relevant to the validity of the SCM. As noted earlier, this model does not take issue with the claim that individuals with DID display relatively distinctive features that are rarely found in other conditions. As useful as the measures of DID and dissociation reviewed by Gleaves might be for diagnostic purposes, they are not designed to differentiate conditions that are largely iatrogenic (or otherwise influenced by social expectancies) from other conditions.
Gleaves' s ( 1996) conclusions concerning the convergent and discriminant relations of the DES with various psychopathological conditions are similarly open 10 alternative explanations. Many DES items (e.g., "Some people find that in one situation they may act so differently compared with another situation that they feel almost as if they were two different people") refer explicitly to common signs and symptoms of DID (Spanos, 1996). As a consequence, the finding that the DES consistently distinguishes DID from other conditions is neither surprising nor informative and might instead by attributed to the largely tautological overlap between the content of DES items and the symptoms of DID.
Although this problem of content overlap is not unique to the literature on DID and probably accounts partly for a number of commonly reported correlations among measures of psychopathology (see Nicholls, Licht, & Pearl, 1982, for a general discussion of this problem in the self-report assessment of personality and psychopathology), it is important to note that Gleaves invoked the correlation between the DES and DID as evidence against the claim that the features of DID are largely iatrogenic (p. 46). [*4] However, this correlation is equally consistent with both an iatrogenic and non-iatrogenic hypothesis, because it can more parsimoniously be explained by content overlap.