Am J Psychiatry 155:6, June 1998 TUTKUN, FREQUENCY ŞAR,O YARGIÇ, F DISSOCIATIVE ET AL. DISORDERS Frequency of Dissociative Disorders Among Psychiatric Inpatients in a Turkish University Clinic Hamdi Tutkun, M.D., Vedat Şar, M.D., L. İ lhan Yargιç, M.D., Tuba Özpulat, M.D., Medaim Yanik, M.D., and Emre Kiziltan, M.D. O bjective: T he aim of this study w as to determine the rate of dissociative disorders among psychiatric inpatients in a university clinic in T urk ey. Method: T he Dissociative Ex periences Scale w as used to screen 166 consecutive inpatients adm itted to the psychiatry clinic of a university hospital. T he patients w ho had scores higher than 30 w ere matched for age and gender w ith 19 of the patients w ho scored below 10 on the scale. T he patients in both groups w ere then interview ed w ith the D issociative D isorders Interview Schedule by interview ers w ho w ere blind to their diagnoses and scores on the D issociative Ex periences Scale. Patients w ho w ere diagnosed as having a dissociative disorder according to the D issociative D isorders Interview Schedule w ere then interview ed by a clinician. R esults: T w enty-four (14.5% ) of the 166 patients had a score higher than 30 on the Dissociative Ex periences Scale; 17 patients (10.2% ) w ere diagnosed as having a dissociative disorder according to the D issociative D isorders Interview Schedule. N ine patients (5.4% ) had clinically confirm ed dissociative identity disorder. Conclusions: A considerable proportion of the psychiatric inpatients in a T urk ish university psychiatry clinic had dissociative disorder. Clinicians w ho w ork in general psychiatric inpatient units should be alert for chronic complex dissociative disorders. (Am J Psychiatry 1998; 155:800–805) D issociative disorders were first officially classified as a separate diagnostic group in DSM -III. Until the last decade, no standardized instrument had been designed to yield uniform diagnoses of dissociative disorders. Structured diagnostic interviews developed for other psychiatric categories did not include assessment of dissociative disorders. The development of objective screening instruments (1, 2) and structured interviews (3, 4) filled this gap and promoted empirical research leading to a change in opinions regarding the relevance of dissociative disorders in psychiatry. Dissociative identity disorder (DSM -IV), also known as multiple personality disorder, has been the most extensively studied dissociative disorder in the last decade (5, 6). It is considered the most severe manifestation of dissociative psychopathology that is closely related to child abuse (7). There is growing interest in this previously neglected diagnostic category among clinicians and researchers in several countries (8–13). Studies conducted with standardized assessment measures in Presented in part at the 13th Fall Conference of the International Society for the Study of Dissociation, San Francisco, N ov. 8, 1996. Received M arch 20, 1997; revision received Aug. 13, 1997; accepted N ov. 14, 1997. From the Clinical Psychotherapy Unit and Dissociative Disorders Program, Department of Psychiatry, Istanbul M edical Faculty, Istanbul University, Istanbul, Turkey. Address reprint requests to Dr. Şar, Istanbul Tip Fakültesi Psikiyatri Klinig^i, 34390 Çapa, Istanbul, Turkey; vsar@prizma.net.tr (e-mail). 800 N orth America (14), The N etherlands (15), and Turkey (16) reported similar symptom profiles, supporting cross-cultural consistency of the disorder. Dissociative symptoms have traditionally been considered quite common in Turkey, especially in emergency psychiatric wards and emergency units of general hospitals (17–19). Dissociative states were usually conceived of as acute and self-limited clinical conditions that tend to be recurrent; an underlying, chronic, complex dissociative psychopathology was never taken into consideration. Dissociative states have been linked to developmental conditions characterized by restriction, oppression, neglect, and even hostile rejection in the family of origin (19–21); however, the relation to childhood traumata, especially sexual and physical abuse, was not included as part of today’s trauma paradigm (22). Consequently, the direct traumatic origins of current symptoms were not taken into consideration in the psychotherapeutic treatment of these patients (23–25). In studies using standardized instruments, we found rates of dissociative identity disorder of 3.9% among psychiatric outpatients (26) and 0.4% in the general population in Turkey (27). We also found that dissociative symptoms are far from rare in studies conducted among nonclinical populations in Turkey (27–29). In the present study, we attempted to determine the rate of dissociative disorders in psychiatric inpatients in Turkey using standardized assessment instruments. To A m J Psychiatry 155:6, June 1998 TUTKUN , ŞAR, YARGIÇ, ET AL. M ETH O D hood abuse and some psychiatric symptoms as part of a concurrent study. Three psychiatry residents (T.Ö ., M .Y., and E.K.) administered the scale to the patients of their own gender. In the second phase of the study, all subjects who had scores higher than 30 on the Dissociative Experiences Scale were matched for age and gender with 19 of the patients who scored below 10 on the scale. The Dissociative Disorders Interview Schedule was administered to patients in both groups. The interviewer was blind to the patients’ diagnoses and Dissociative Experiences Scale scores. All structured interviews were conducted by two of us (H .T. and L. İ .Y.), both of whom had extensive experience using this instrument before the initiation of the study. In the third phase of the study, all subjects who were diagnosed as having a dissociative disorder according to the Dissociative Disorders Interview Schedule were interviewed for clinical confirmation. Personality switches were observed at least three times in patients who were diagnosed as having dissociative identity disorder. Because we were all working at the same institution, it was not possible to keep the clinician in the third phase (H .T.) blind to the data obtained during the second phase. O ne of us (V.Ş.), a psychiatrist and director of the Dissociative Disorders Program and the Clinical Psychotherapy Unit, confirmed all of the clinical diagnoses either by direct consultation or supervision. Subjects D ata A nalysis All patients admitted to two 30-bed general psychiatric inpatient wards at the Istanbul M edical Faculty H ospital over a 7-month period (N ovember 1, 1994, to M ay 31, 1995) were considered for participation in the study. Patients who had previously been diagnosed as having a dissociative disorder were excluded from the study. The patients who agreed to participate in the study provided written informed consent after the study procedures had been fully explained. All patients were approached for the study if their treating physician felt that they could give informed consent and there were no other clinical limitations on their participation. Some of the patients were allowed to stabilize for 1 to 2 weeks before being asked to give informed consent. The comparison subjects were drawn from the same patient population. Subjects who completed the Dissociative Experiences Scale were compared with those who did not complete the scale to determine whether these two groups differed in gender or age. The frequency of dissociative disorders was calculated on the basis of the number of subjects who received a confirming clinical diagnosis from a clinician. Characteristics of patients with diagnoses of a dissociative disorder were compared with those of patients with no dissociative disorder. Student’s two-tailed t tests were used to compare ordinal data. Chisquare analyses were used to compare nominal data. Bonferroni correction for multiple comparisons was used. Instrum ents During the research period, 261 consecutive patients were admitted to the inpatient wards. Twenty patients were excluded for the following reasons: six had been previously diagnosed as having dissociative identity disorder, six had mental retardation, and eight were illiterate. O f the 241 remaining patients, 166 (68.9% ) completed the questionnaires (63.6% of all admissions). The reasons for not completing the questionnaires included being hospitalized for too short a time, refusal to participate, or being too psychotic to be invited. There was no significant difference in the ages of the patients who did not participate (mean=31.6 years, SD=11.3) and those patients who did (mean=32.1 years, SD =1 2 .0 ) (t =0 .3 3 , d f=2 3 1 , p>0.05). Twenty-one (8.7% ) of the 241 patients were younger than 18. Women made up 58.4% (N =97) of those who completed the questionnaires and 53.3% (N =40) of those who did not complete them; this difference was not significant (χ2 =1.25, df=2, p>0.05). The age range of the participating patients was 13–70 years. There was no significant difference in age between women (mean=32.0, SD=12.2) and men (mean=32.3, SD=11.8) (t=0.16, df= 164, p>0.05). The mean Dissociative Experiences Scale rating of the original 166 patients was 17.8 (SD=14.9, range=0.0– 77.9, median=14.6). Twenty-four (14.5% ) of the 166 our knowledge, this is the first study scanning dissociative identity disorder among psychiatric inpatients in our country. We also attempted to determine the differences between patients with the diagnosis of dissociative disorder and those who reported few dissociative symptoms. An additional reason for using such a comparison group and interviewing the two groups in a blind fashion was to eliminate bias in the assessment of these patients. To eliminate any false positive findings, all patients given the diagnosis of a dissociative disorder according to results of the structured interview were evaluated by a clinician. Additionally, information about the frequency of childhood abuse, suicide attempts, and self-mutilative behavior was gathered by using a self-report questionnaire; details of related results will be published elsewhere. 1. D issociative Ex periences Scale. The Dissociative Experiences Scale (1) is a 28-item self-report instrument. It is not a diagnostic tool but serves as a screening device for chronic dissociative disorders. Possible scores range from 0 to 100. M edian scores on this scale have been shown to differentiate patients with a chronic dissociative disorder from patients with other psychiatric conditions (1, 30). The Turkish version of the scale has reliability and validity (31) as high as those of its original form. 2. D issociative D isorders Interview Schedule. The Dissociative Disorders Interview Schedule (3) is a structured interview consisting of 131 items. It is used to make DSM -III-R diagnoses of somatization disorder, major depressive episode, borderline personality disorder, and all the dissociative disorders. This schedule also inquires about childhood physical and sexual abuse and a variety of features associated with dissociative identity disorder, including 11 Schneiderian symptoms, 16 secondary features of dissociative identity disorder, and 16 extrasensory experiences. Two items inquiring about childhood emotional abuse and neglect that are not included in the English form of the schedule were added to the Turkish version. The schedule has an overall interrater reliability of 0.68 (kappa), a sensitivity of 90% , and a specificity of 100% for the diagnosis of dissociative identity disorder (11). Information on the validity and reliability of the Turkish version has been reported elsewhere (16, 32). Procedure The study consisted of three phases. In the first phase, all patients were asked to complete the Dissociative Experiences Scale. They also completed a self-report questionnaire gathering information on child- A m J Psychiatry 155:6, June 1998 RESULTS 801 FREQ UEN CY O F DISSO CIATIVE DISO RDERS tients had other diagnoses: one had posttraumatic stress disorder (PTSD) and three had schizophrenic disorder. N one of the patients with Dissociative Experiences Scale scores below 10 had the diagnosis of a dissociative Dissociative Disorder Present According to disorder (table 1). Sensitivity and specificity were 100% Dissociative Disorders and 83% , respectively, positive predictive power was Interview Schedule 81% , and negative predictive power was 100% . Yes No Total Eleven (eight women and three men) of the 17 patients (N =17) (N =23) (N =40) Group with a dissociative disorder had the diagnosis of dissociative identity disorder according to the Dissociative Patients with Dissociative Experiences Scale score >30 (N =21) 17 4 21 Disorders Interview Schedule. The remaining six patients Patients with Dissociative Experiwere diagnosed as having dissociative disorder not othences Scale score <10 (N =19) 0 19 19 erwise specified. Dissociative identity disorder and disa Yates-corrected χ2 =26.65, df=1, p<0.00001. sociative disorder not otherwise specified were considered supraordinate diagnoses. Any patient who met criteria for TABLE 2 . Main Symptom Cluster Scores on the Dissociative Disorders Interview Schedule of Psydissociative amnesia, dissociaa chiatric Inpatients With or Without Diagnoses of Dissociative Disorder tive fugue, or depersonalization Patients Patients disorder and also met criteria With Without for dissociative identity disorDissociative Dissociative der or dissociative disorder not Disorder Disorder (N =17) (N =19) Student’s t Test otherwise specified received the overall diagnosis of either dissoVariable M ean SD M ean SD t (df=34) p ciative identity disorder or disSymptom cluster sociative disorder not otherwise Secondary features of dissociative idenspecified. tity disorder 9.4 3.8 0.8 1.1 11.28 <0.001 Nine patients (seven women Extrasensory perceptions 4.5 2.3 1.3 1.7 4.74 <0.001 and two men) were diagnosed Schneiderian symptoms 6.4 2.8 1.6 2.0 5.99 <0.001 Borderline personality disorder criteria 5.6 2.1 1.0 1.1 8.15 <0.001 as having dissociative identity Somatic complaints 10.5 4.1 1.7 2.2 8.14 <0.001 disorder by clinical examinaDissociative Experiences Scale score 48.3 14.7 5.0 2.8 12.60 <0.001 tion. The remaining eight paAge (years) 24.7 11.6 29.4 8.7 1.37 n.s. tients were diagnosed as having a Patients with dissociative disorder had scores greater than 30 on the Dissociative Experiences Scale dissociative disorder not otherand were given the diagnosis on the basis of the Dissociative Disorders Interview Schedule; patients wise specified. In six of these pawithout dissociative disorder had scores less than 10 on the Dissociative Experiences Scale. tients, some personality states were observed repeatedly, but they were not considered sufficiently distinct and sepapatients had a score higher than 30, and 56 (33.7% ) rate to diagnose a dissociative identity disorder at this had a score higher than 20. Women (mean=19.7, SD= stage of the evaluation. A 45-year-old male patient from 16.9) had a higher score than men (mean=15.0, SD=11.0) this group had the diagnosis of dissociative identity dis(t=2.04, df=164, p<0.05). Age correlated negatively with order according to the Dissociative Disorders Interview scale score (r=–0.27, N=166, p<0.001). Six of the patients Schedule, but he declared that he did not want his alter with a score higher than 30 were men and 18 were women. personalities to be evaluated. However, there was no difference in gender between Findings from the main symptom clusters of the Dissopatients with a score higher than 30 and those with a ciative Disorders Interview Schedule and the Dissociative score of 30 or lower (χ2 =3.17, df=1, p>0.05). Patients Experiences Scale scores for the two groups are presented with scores above 30 (mean age=27.0, SD=11.4) were in table 2. The patients with a dissociative disorder had younger than those with scores of 30 or lower (mean significantly higher scores in all main symptom clusters age=33.0, SD=12.0) (t=2.28, df=164, p<0.05). and on the Dissociative Experiences Scale. Twenty-one of the 24 patients with scores above 30 Table 3 indicates the Dissociative Disorders Intercould be evaluated with the Dissociative Disorders Inview Schedule diagnoses that the patients in both terview Schedule. Two patients were hospitalized for groups received. All patients in the dissociative disortoo short a period, and one refused to participate in the ders group met DSM -III-R criteria for a dissociative disinterview. This sole refusing patient told the interviewer order. M ost of them had comorbid psychiatric disorthat he was deeply affected by the content of the Dissoders. There were high rates of comorbid borderline ciative Experiences Scale and was afraid that a further personality disorder, current or past episode of major evaluation “ might elicit something” in him. depression, and somatization disorder. Seventeen of the 21 patients with Dissociative ExpeTable 4 shows some findings concerning mental health riences Scale scores above 30 were diagnosed as having history derived from the Dissociative Disorders Interview a dissociative disorder according to the Dissociative Schedule. Significantly more patients in the dissociative Disorders Interview Schedule. The remaining four paTABLE 1 . Relation of Dissociative Disorder Diagnosis Made With Dissociative Disorders Interview Schedule to Scores on Dissociative Experiences Scale for 4 0 Psychiatric Inpatientsa 802 A m J Psychiatry 155:6, June 1998 TUTKUN , ŞAR, YARGIÇ, ET AL. disorders group than in the comparison group reported physical abuse and sexual abuse (table 4). More of the patients with dissociative disorder than patients in the comparison group also reported emotional abuse. Sixteen of the 17 patients in the dissociative disorders group had contacted a psychiatrist previously. The mean interval between their first psychiatric contact and the study interview was 4.6 years (SD=4.6, range=3 months–15 years). Seven of these patients had been hospitalized at least once (range=1–6 times). Nine had been given diagnoses of depression, one mania, two schizophrenic disorder, and two anxiety disorder. Eleven had been prescribed psychotropic medication. Two of the subjects had received ECT; nine had received antipsychotic medication, 13 had received an antidepressant, and two had received lithium. Fourteen of the subjects said that they had received ineffective treatment at some time. Only five of the subjects had received courses of psychotherapy. For all but one of them the psychotherapeutic intervention ceased in fewer than 10 sessions. The only exception was an incest victim with the diagnosis of depressive disorder who had received both biological and psychotherapeutic treatment for 6 years; her care was covered by a women’s shelter in Istanbul (Mor Cati [Purple Roof]). DISCUSSIO N TABLE 3 . Dissociative Disorders Interview Schedule Diagnoses of Psychiatric Inpatients With or Without Diagnoses of Dissociative Disordera Patients With Dissociative Disorder (N =17) Patients Without Dissociative Disorder (N =19) Chi-Square Analysisb Diagnosis N % N % χ2 (df=1) p Major depression (current or past) Borderline personality disorder Somatization disorder Any comorbid disorder Dissociative amnesia Depersonalization disorder Dissociative fugue Dissociative disorder not otherwise specified Dissociative identity disorder 14 12 6 16 14 14 5 82.4 70.6 35.3 94.1 82.4 82.4 29.4 9 0 0 9 0 1 0 47.4 0.0 0.0 47.4 0.0 5.3 0.0 4.76 20.12 17.70 9.24 25.60 21.94 —c n.s. <0.00005 <0.00005 <0.005 <0.00001 <0.00001 n.s. 3 14 17.6 82.4 0 0 0.0 0.0 —c 25.60 n.s. <0.00001 a Patients with dissociative disorder had scores greater than 30 on the Dissociative Experiences Scale and were given the diagnosis on the basis of the Dissociative Disorders Interview Schedule; patients without dissociative disorder had scores less than 10 on the Dissociative Experiences Scale. b The adapted level of alpha is p=0.005 when the Bonferroni method is applied. cFisher’s exact test. TABLE 4 . Gender and Dissociative Disorders Interview Schedule Mental Health History Items of Psychiatric Inpatients With or Without Diagnoses of Dissociative Disordera Patients With Dissociative Disorder (N =17) Patients Without Dissociative Disorder (N =19) Chi-Square Analysisb Variable N % N % χ2 (df=1) p Gender (female) Dissociative Disorders Interview Schedule mental health history items Self-mutilation Suicide attempt Substance abuse H eadache Trance Childhood imaginary companionship Somnambulism Sexual abuse Sexual and/or physical abuse Physical abuse Emotional abuse N eglect Any type of abuse 13 76.5 13 68.4 0.28 n.s. 15 14 5 14 17 5 5 10 14 14 12 10 15 88.2 82.4 29.4 82.4 100.0 29.4 29.4 58.8 82.4 82.4 70.6 58.8 88.2 4 6 0 4 6 0 2 1 5 4 2 4 6 21.1 31.6 0.0 21.1 31.6 0.0 10.5 5.3 26.3 21.1 10.5 21.1 31.6 16.15 9.36 —c 13.49 18.20 —c —c 13.20 11.30 15.35 16.70 7.20 11.85 <0.0001 n.s. n.s. n.s. <0.00005 n.s. n.s. <0.0005 <0.001 <0.0001 <0.00005 n.s. <0.001 a Patients with dissociative disorder had scores greater than 30 on the Dissociative Experiences O f all consecutively admitted Scale and were given the diagnosis on the basis of the Dissociative Disorders Interview Schedule; patients without dissociative disorder had scores less than 10 on the Dissociative Experiences patients to an inpatient psychiatScale. ric unit, 63.6% could be recruited b The adapted level of alpha is p=0.003 when the Bonferroni method is applied. for the present study. This rate is cFisher’s exact test. similar to those of Ross et al. (33) and Saxe et al. (34) and higher To our knowledge, there are few studies using a structhan those of Latz et al. (35) and Modestin et al. (36). On tured interview to determine the rate of dissociative disthe basis of our findings in the current study, the conserorders among psychiatric inpatients (13, 33–36). Table vative estimate of the frequency of new cases of dissocia5 presents the results from several studies. The rates in tive disorders among psychiatric inpatients is 10.2% , inour study are in agreement with those of studies in cluding 5.4% with dissociative identity disorder. These N orth America and N orway despite the higher cutoff are the percentages of subjects who received the diagnosis score in our first phase. A study on a Swiss sample (36) from both the Dissociative Disorders Interview Schedule found lower rates. Whether this difference depends on and the study clinician. A m J Psychiatry 155:6, June 1998 803 FREQ UEN CY O F DISSO CIATIVE DISO RDERS TABLE 5 . Studies of Dissociative Disorder Among Psychiatric Inpatients Study N umber of Subjects Present study 166 Modestin et al. (36) 207 Knudsen et al. (13) 101 Latz et al. (35) 176 c Saxe et al. (34) 110 Ross et al. (33) 299 a Clinically confirmed diagnosis. Diagnostic Instrument Cutoff on Dissociative Experiences Scale Dissociative Disorders Interview Schedule Dissociative Disorders Interview Schedule Structured Clinical Interview for Dissociative Disorders Dissociative Disorders Interview Schedule Dissociative Disorders Interview Schedule Dissociative Disorders Interview Schedule b Data not given. cultural influences or is caused by different inpatient sample characteristics is not yet known. M ost of the patients with dissociative disorders in our study group had comorbid psychiatric disorders according to the structured interview. There were high rates of comorbid borderline personality disorder, current or past episode of major depression, and somatization disorder. Approximately two-thirds of our study group met criteria for borderline personality disorder. This finding is in agreement with that of Saxe et al. (34). However, in a case series of mostly outpatients with dissociative identity disorder (16), we found that the rate of borderline personality disorder was much lower, suggesting that patients fitting these criteria are hospitalized more frequently. It is not uncommon for patients with dissociative identity disorder to meet DSM -IV criteria for several other disorders at the same time (14–16). Although dissociative identity disorder and borderline personality disorder have their own diagnostic features, there is a wide phenomenological overlap. O n the other hand, M odestin et al. (36) determined that Dissociative Experiences Scale scores correlated positively with a number of features of practically all personality disorder subtypes. Significantly higher rates of childhood traumatic experiences were found in our patients with a dissociative disorder than in the comparison group. This finding supports the notion that traumatic childhood experiences play a major role in the development of dissociative disorders (7, 22). Saxe et al. (34) found that PTSD was also frequent among inpatients with a dissociative disorder. Self-destructive behavior such as self-mutilation, suicide attempts, and substance abuse were also common in our dissociative disorder group. This type of behavior also has been linked to childhood trauma (37). The Dissociative Experiences Scale ratings of our in- 804 Rate of Dissociative Identity Disorder (% ) Dissociative Experiences Scale Score Rate of Dissociative Disorder (% ) Mean SD Patients With Score >30 (% ) 30 5.4 a 10.2 a 17.8 14.9 14.5 20 0.4 5.0 13.7 13.5 12.0 30 3.0 6.0 — N one 12.0 — b b — b — — b b 15.0 b 34.7 b b 25 4.0 15.0 — — — 20 3.3 a 20.7 14.6 14.2 15.4 c Subjects included only females. patients are similar to those obtained in comparable study groups in N orth America (33–35, 38) and Europe (13, 37). Among patients with Dissociative Experiences Scale scores higher than 30, 81.0% of evaluated patients suffered from a clinically confirmed, chronic, complex dissociative disorder; this finding confirms that high scores on the scale are highly suggestive of a dissociative disorder. In our study, women had a higher mean Dissociative Experiences Scale score than men. That Dissociative Experiences Scale scores of men and women do not differ in the general population (27, 39) and among patients with different psychiatric disorders (35) suggests that women with dissociative symptoms are hospitalized more frequently. Results reported by Chu and Dill (38) and Latz et al. (35) support this idea. Because these studies had few (38) or no (35) male subjects, their results are not comparable with ours. Some of the previous studies (40, 41) pointed out that childhood traumata are more common among women. CO N CLUSIO N S There is accumulating evidence suggesting that dissociative disorders are frequent among psychiatric inpatients. We found that approximately 10% of the psychiatric patients in a Turkish university hospital met the criteria for a chronic complex dissociative disorder. H alf of these patients met the criteria for dissociative identity disorder. Patients who have chronic complex dissociative disorder are very likely to fit the criteria for borderline personality disorder, somatization disorder, and at least one major episode of major depression as well. These individuals are also very likely to have had a history of childhood abuse and neglect. They present a challenge for psychiatrists working in inpatient units. Q uasi-psychotic posttraumatic symptoms of these pa- A m J Psychiatry 155:6, June 1998 TUTKUN , ŞAR, YARGIÇ, ET AL. tients can easily lead to diagnostic errors. An accurate diagnosis is crucial for better intervention and management. Dissociative disorders should be investigated routinely in psychiatric assessments. The use of structured instruments is helpful for this purpose. 22. REFEREN CES 23. 1. Bernstein EM , Putnam FW: Development, reliability, and validity of a dissociation scale. J N erv M ent Dis 1986; 174:727–735 2. Vanderlinden J, Van Dyck R, Vandereycken W, Vertommen H : The Dissociation Q uestionnaire (DIS-Q ): development and characteristics of a new self-reporting questionnaire. Clin Psychol Psychotherapy 1991; 1:21–27 3. Ross CA, H eber S, N orton GR, Anderson D, Anderson G, Burchet P: The Dissociative Disorders Interview Schedule: a structured interview. Dissociation 1989; 2:169–189 4. Steinberg M , Rounsaville B, Cicchetti DV: The Structured Clinical Interview for DSM -III-R Dissociative Disorders: preliminary report on a new diagnostic instrument. Am J Psychiatry 1990; 147:76–82 5. Putnam FW, Guroff JJ, Silberman EK, Barban L, Post RM : The clinical phenomenology of multiple personality disorder: review of 100 recent cases. J Clin Psychiatry 1986; 47:285–293 6. Ross CA, N orton GR, Wozney K: M ultiple personality disorder: an analysis of 236 cases. Can J Psychiatry 1989; 34:413–418 7. Kluft RP: M ultiple personality disorder, in American Psychiatric Press Review of Psychiatry, vol 10. Edited by Tasman A, Goldfinger SM . Washington DC, American Psychiatric Press, 1991, pp 161–188 8. Adityanjee, Raju GSP, Khandelwal SK: Current status of multiple personality disorder in India. Am J Psychiatry 1989; 146: 1607–1610 9. Takahashi Y: Is multiple personality disorder really rare in Japan? Dissociation 1990; 3:57–59 10. M artinez-Taboas A: M ultiple personality in Puerto Rico: an analysis of fifteen cases. Dissociation 1991; 4:189–192 11. Modestin J: M ultiple personality disorder in Switzerland. Am J Psychiatry 1992; 149:88–92 12. Tutkun H , Yargιç Lİ , Şar V: Dissociative identity disorder: clinical investigation of 20 cases from Turkey. Dissociation 1995; 8:3–9 13. Knudsen H , H aslerud J, Boe T, Draijer N , Boon S: Prevalence of dissociative disorders in a N orwegian general psychiatric department (inpatients and daycare), in Proceedings of the Fifth Annual M eeting of the International Society for the Study of Dissociation. Edited by van der H art O , Boon S, Draijer N . Amsterdam, International Society for the Study of Dissociation, 1995, p 79 14. Ross CA, M iller SD, Reagor P, Bjornson L, Fraser GA, Anderson G: Structured interview data on 102 cases of multiple personality disorder from four centers. Am J Psychiatry 1990; 147:596–601 15. Boon S, Draijer N : M ultiple personality disorder in The N etherlands: a clinical investigation of 71 patients. Am J Psychiatry 1993; 150:489–494 16. Şar V, Yargιç Lİ , Tutkun H : Structured interview data on 35 cases of dissociative identity disorder in Turkey. Am J Psychiatry 1996; 153:1329–1333 17. Ö ztürk O M , Volkan VD: The theory and practice of psychiatry in Turkey. Am J Psychother 1971; 15:240–271 18. Salgirtay A: [An Evaluation of Emergency Admissions to Ankara University Psychiatry Clinic] (doctoral dissertation). Ankara, Turkey, Ankara University M edical Faculty, Department of Psychiatry, 1979 (Turkish) 19. Ö ztürk O M , GöG^üş A: [H ysterical psychosis presenting with severe regressive symptoms], in Proceedings of the 9th N ational Congress of Psychiatry and N eurology. Ankara, M eteksan, 1973, pp 155–164 (Turkish) 20. Ö ztürk O M : [H ysterical neurosis], in [Textbook of M ental H ealth and Diseases]. Edited by Ö ztürk O M . Ankara, M eteksan, 1981, pp 209–219 (Turkish) 21. Şar İ : [A Retrospective Evaluation of Inpatients Diagnosed as 24. A m J Psychiatry 155:6, June 1998 25. 26. 27. 28. 29. 30. 31. 32. 33. 34. 35. 36. 37. 38. 39. 40. 41. H aving “ H ysteria” in H acettepe University Psychiatry Clinic Between 1970–1980] (doctoral dissertation). Ankara, Turkey, H acettepe University M edical Faculty, Department of Psychiatry, 1983 (Turkish) Spiegel D: Dissociation and trauma, in American Psychiatric Press Review of Psychiatry, vol 10. Edited by Tasman A, Goldfinger SM . Washington, DC, American Psychiatric Press, 1991, pp 261–275 Tutkun H , Yargιç Lİ , Şar V: Dissociative identity disorder presenting as hysterical psychosis. Dissociation 1996; 9:244–252 Şar V, Yargιç Lİ , Tutkun H : [Sociodemographic and clinical features of 25 patients with dissociative identity disorder: results of long-term evaluation and treatment]. Düsünen Adam 1995; 8: 38–46 (Turkish) Şar V, Yargιç Lİ , Tutkun H : Current status of dissociative identity disorder in Turkey, in Proceedings of the Fifth Annual M eeting of the International Society for the Study of Dissociation. Edited by van der H art O , Boon S, Draijer N . Amsterdam, International Society for the Study of Dissociation, 1995, p 76 Şar V, Tutkun H , Alyanak B, Bakim B, Baral I: Frequency of dissociative identity disorder among psychiatric outpatients in a Turkish university clinic, in Program Book, 13th Fall Conference of the International Society for the Study of Dissociation. Glenview, Ill, International Society for the Study of Dissociation, 1996, p 141 Akyüz G, DoG^an O , Şar V, Yargιç Lİ , Tutkun H : Frequency of dissociative identity disorder in the general population: an epidemiologic study on a representative sample from a city in Central Turkey. Ibid, p 143 Z oroG^lu S, Tuzun U, Şar V, Erocal-Kora M , Ö ztürk M , Alyanak B: Childhood abuse, self-injury and dissociative experiences among high-school students. Ibid, p 285 Yargιç Lİ , Tutkun H , Şar V: Childhood abuse and dissociative experiences in adulthood, in Proceedings of the Fifth Annual Meeting of the International Society for the Study of Dissociation. Edited by van der H art O , Boon S, Draijer N . Amsterdam, International Society for the Study of Dissociation, 1995, p 84 Carlson EB, Putnam FW, Ross CA, Torem M , Coons P, Dill DL, Loewenstein RJ, Braun BG: Validity of the Dissociative Experiences Scale in screening for multiple personality disorder: a multicenter study. Am J Psychiatry 1993; 150:1030–1036 Yargιç Lİ , Tutkun H , Şar V: The reliability and validity of the Turkish version of the Dissociative Experiences Scale. Dissociation 1995; 8:10–13 Yargιç Lİ , Şar V, Tutkun H : [Differential diagnosis of multiple personality disorder using a self-rating scale (DES) and a structured clinical interview schedule (DDIS)], in [Proceedings of the 31st N ational Congress of Psychiatry]. Istanbul, Turkish N europsychiatric Society, 1995, p 70 (Turkish) Ross CA, Anderson G, Fleisher WP, N orton GR: The frequency of multiple personality disorder among psychiatric inpatients. Am J Psychiatry 1991; 148:1717–1720 Saxe GN , van der Kolk BA, Berkowitz R, Chinman G, H all K, Lieberg G, Schwartz J: Dissociative disorders in psychiatric inpatients. Am J Psychiatry 1993; 150:1037–1042 Latz TT, Kramer SI, H ughes DL: M ultiple personality disorder among female inpatients in a state hospital. Am J Psychiatry 1995; 152:1343–1348 M odestin J, Ebner G, Junghan M , Erni T: Dissociative experiences and dissociative disorders in acute psychiatric inpatients. Compr Psychiatry 1996; 37:355–361 van der Kolk BA, Perry JC, H erman JL: Childhood origins of self-destructive behavior. Am J Psychiatry 1991; 148:1665–1671 Chu JA, Dill LD: Dissociative symptoms in relation to childhood physical and sexual abuse. Am J Psychiatry 1990; 147:887–892 Ross CA, Joshi S, Currie R: Dissociative experiences in the general population. Am J Psychiatry 1990; 147:1547–1552 Jacobson A, H erald C: The relevance of childhood sexual abuse to adult psychiatric inpatient care. H osp Community Psychiatry 1990; 41:154–158 Brown GR, Anderson B: Psychiatric morbidity in adult inpatients with childhood histories of sexual and physical abuse. Am J Psychiatry 1991; 148:55–61 805