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Abstract

Purpose The main objective of this study was to test the psychometric properties of the Polish version of SDQ-20 and the capacity of this instrument, alongside a set of five questions derived from it (SDQ-5), to screen for dissociative disorders. The Somatoform Dissociation Questionnaire (SDQ-20) has been used in many language versions to evaluate the severity of somatoform dissociative symptoms, but no such tool has existed in Polish. Basic procedures Both pen-and-paper (p&p) and online versions of SDQ-20 were tested. Validity and reliability were examined in a sample of 597 participants in non-clinical (N = 323) and clinical (N = 274) groups, who completed the tests p&p (N = 79) or online (N = 518). The mixed-clinical group included 20 patients diagnosed with dissociative (conversion) disorders using TADS-I, and people with other disorders. Main findings The Exploratory Factor Analysis with Principal Component Analysis method of parameter estimation without rotation confirmed unidimensionality of p&p and online versions of SDQ-20. Psychometric properties of the original SDQ-5 were unsatisfactory. Subsequently, an alternative version (PSDQ-5) with a different set of questions derived from SDQ-20 was examined. Reliability of both versions was corroborated by a Cronbach's alpha coefficient (SDQ-20 > .84, PSDQ-5 > .74). The cutoff score maximising sensitivity and specificity was 29.5 (SDQ-20) and 7.5 (PSDQ-5) for dissociative (conversion) disorders (SDQ-20: sensitivity of 95.0% and specificity of 75.6%; PSDQ-5: sensitivity of 95.0% and specificity of 65.9%). People with dissociative disorders had significantly (p< .001) higher scores in SDQ-20 and PSDQ-5 than patients with other disorders and non-clinical participants (criterion validity). Principal conclusion SDQ-20, administered p&p or online, proved to be a reliable tool for the screening of dissociative disorders in Poland. An alternative set of five questions (PSDQ-5) derived from the main instrument also presented good psychometric properties.

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... Potential candidates enrolled themselves or were registered by healthcare providers via an application integrated with the website www.e-psyche.eu. They filled in demographic information and completed online tests, including: Somatoform Dissociation Questionnaire (SDQ-20, Pietkiewicz et al., 2018) and Trauma Experiences Checklist (Nijenhuis et al., 2002). Those with elevated SDQ-20 scores (above 28 points) or those referred for differential diagnosis were consulted and if dissociative symptoms were confirmed, they were invited to participate in an in-depth clinical assessment including a series of interviews, video-recorded and performed at the researcher's office by the first author who is a psychotherapist and supervisor experienced in the dissociation field. ...
... They also revealed a tendency to indulge themselves in these auto-critical thoughts instead of actively avoiding them, which is often a case in dissociative patients. Some intrusions reported by DID patients are somatoform in nature and connected with dissociative parts stuck in trauma time (Pietkiewicz et al., 2018). Although three participants in this study had very high scores in SDQ-20 indicating that they may have a dissociative disorder (scores of 50-60 are common in DID), further interviews revealed that they aggravated their symptoms and, in fact, had low levels of somatoform dissociation. ...
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ICD-10 and DSM-5 do not provide clear diagnosing guidelines for DID, making it difficult to distinguish ‘genuine’ DID from imitated or false-positive cases. This study explores meaning which patients with false-positive or imitated DID attributed to their diagnosis. 85 people who reported elevated levels of dissociative symptoms in SDQ-20 participated in clinical assessment using the Trauma and Dissociation Symptoms Interview, followed by a psychiatric interview. The recordings of six women, whose earlier DID diagnosis was disconfirmed, were transcribed and subjected to interpretative phenomenological analysis. Five main themes were identified: 1) Endorsement and identification with the diagnosis. 2) The notion of dissociative parts justifies identity confusion and conflicting ego-states. 3) Gaining knowledge about DID affects the clinical presentation. 4) Fragmented personality becomes an important discussion topic with others. 5) Ruling out DID leads to disappointment or anger. To avoid misdiagnoses, clinicians should receive more systematic training in the assessment of dissociative disorders, enabling them to better understand subtle differences in the quality of symptoms and how dissociative and non-dissociative patients report them. This would lead to a better understanding of how patients with and without a dissociative disorder report core dissociative symptoms. Some guidelines for a differential diagnosis are provided.
... Positive somatoform symptoms involve reactivation of state-dependent or traumaassociated responses and are exemplified by: localised pain, involuntary movements without neurological cause, sensation of smell and taste without a stimulus (Nijenhuis, 2015;van der Hart et al., 2006;Waller et al., 2001). These symptoms can be measured by the Somatoform Dissociation Questionnaire (SDQ-20, Nijenhuis, 2000Nijenhuis, , 2010Pietkiewicz, Hełka, & Tomalski, 2018). Examples of the negative psychoform symptoms include: amnesia, some forms of depersonalisation, derealisation, and loss of knowledge or skills. ...
... The same cutoff point was identified in a study validating the Polish version of this instrument . Abbreviated five-item versions of SDQ-20 to screen for dissociative disorders were also created in Dutch SDQ-5, (Nijenhuis et al., 1997) or Polish (PSDQ-5, Pietkiewicz et al., 2018), and they had good psychometric properties, unlike other short versions that instrument tested in German (Mueller-Pfeiffer et al., 2010) or Spanish (Gonzalez-Vazquez et al., 2017). ...
Article
Objective: This study tests psychometric properties of the Polish Dissociative Experiences Scale (DESR-PL) with a revised scoring system and its capacity, alongside its short form (DESR-T), to screen for dissociative disorders. Both pen-and-paper (p&p) and online forms were tested. Method: Validity and reliability were examined in a sample of 540 participants in non-clinical (N = 289) and clinical (N = 251) groups, who completed the tests p&p (N = 60) or online (N = 480). The clinical group included 21 patients with dissociative (conversion) disorders, and people with other disorders. The Exploratory Factor Analysis with Principal Component Analysis method of parameter estimation without rotation confirmed unidimensionality of p&p and online versions of DESR-PL and DESR-T. Results: Reliability of both versions was corroborated by a Cronbach’s alpha coefficient (DESR-PL: online > .931 p&p > .937; DESR-T: online > .783 p&p > .797). The cutoff score maximising sensitivity and specificity for dissociative (conversion) disorders was 71.5 in DESR-PL (sensitivity of 71.43% and specificity of 91.82%) and 16.5 in DESR-T (sensitivity of 76.19% and specificity of 92.73%). People with dissociative disorders had significantly (p<.001) higher scores in DESR-PL and DESR-T than patients with other disorders and non-clinical participants (criterion validity). Both DESR-PL and DESR-T strongly correlated with SDQ-20 and PSDQ-5. Conclusions: DESR-PL administrated p&p or online proved to be reliable tools for measuring the levels of dissociation as a continuum between normal experiences and pathological symptoms. DESR-T has similar psychometric properties and can be used effectively for the screening of dissociative disorders.
... or were registered by healthcare providers. They filled in demographic information and completed screening tests for dissociation: Dissociative Experiences Scale-Revised (DESR-PL) [19] and Somatoform Dissociation Questionnare (SDQ-20) [20]. This was followed by a semi-structured interview exploring their biography, family situation, and motives for enrolling in the study, a diagnostic consultation based on the Trauma and Dissociation Symptoms Interview (TADS-I), and a mental state assessment [21]. ...
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Background: Delusional misidentification is a psychotic symptom relating to misidentifying one’s own or someone else’s identity, objects, places, or events. Although rare cases of dissociative amnesia comorbid with psychotic episodes are discussed in literature, there are no such reports referring to the delusional misidentification syndrome. Methods: This study describes a 42-year-old Polish female with a history of three hospitalizations for schizophrenia, during which she had problems with memory and was confused about her identity. She was subjected to clinical assessment using the Trauma and Dissociation Symptom Interview, and a mental state examination was performed by a psychiatrist. Results: The participant reported generalized amnesia for identity and life history accompanied by the Capgras syndrome and reverse intermetamorphosis-like symptoms. She avoided discussing these symptoms, focusing instead on her somatic problems. Discussion: This case illustrates an interaction between dissociative symptoms of amnesia, depersonalization/derealization, and psychotic symptoms in the formation of a delusional misidentification syndrome. It is important to explore in depth the dissociative symptomatology in patients with schizophrenia spectrum disorders.
... Potential candidates enrolled themselves via an application integrated with a dedicated website, or were registered by healthcare providers and pastoral counselors. They filled in demographic information and completed online tests, including: Somatoform Dissociation Questionnaire (SDQ-20, Pietkiewicz et al., 2018), Dissociative Experiences Scale -Revised (DESR, I. . Elevated scores in these tests, SDQ-20 ≥ 30 and DESR ≥72, are suggestive of dissociative disorders. ...
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In many cultures, people use the concept of spirit possession to explain abrupt changes in behavior and identity or problems with affect regulation. High incidence of traumatic experiences are also found among “possession” victims but there are few studies exploring in detail their clinical presentations. This study reports the symptoms of two women with a history of sexual abuse, labeled in their religious communities as possessed, and subjected to exorcisms. Following a thorough clinical assessment, interpretative phenomenological analysis was used to explore their meaning-making and help-seeking behavior. Accepting the demonic reappraisal of trauma-related symptoms and interventions offered by clergy contributed to receiving social support but discouraged them from seeking diagnostic consultations and trauma-focused therapy, leading to their continued symptoms. This justifies the need for educating religious leaders in recognizing and understanding basic psychopathological symptoms.
... The sensitivity and specificity were more satisfactory for the SDQ-20 (Tsar et al., 2001). In a Polish mixed clinical and non-clinical sample, the internal consistency of an online and a pen and paper (p&p) version of SDQ-5 was unsatisfactory (p&p: ⍺ = 0.590; online: ⍺ = 0.518) (Pietkiewicz et al., 2019). performance has not been tested in a population of complex dissociative disorders (Carlson et al., 2018) and is yet not validated in a Danish sample. ...
Article
Objective The structure of the relationship between ICD-11 Complex Post-traumatic Stress Disorder (C-PTSD) and dissociative symptoms requires more extensive research, especially with respect to the empirical support for a DSM-5 dissociative subtype of PTSD. The present study sought to examine (1) the structural validity of ICD-11 C-PTSD, (2) the association between latent C-PTSD factors and features of dissociation, and (3) whether patients with C-PTSD show elevated levels of dissociation when compared to PTSD and no-disorder. Methods A sample of traumatized psychiatric outpatients (N = 114) were diagnosed with a structured interview and subsequently administered the International Trauma Questionnaire (ITQ), the Dissociative Symptom Scale (DSS), and the Somatoform Dissociation Questionnaire, 5-items (SDQ). We used Confirmatory Factor Analysis (CFA) to replicate the established structure of C-PTSD as operationalized with the ITQ. Subsequently, a structural equation model (SEM) approach was employed to examine associations of ITQ with psychoform and somatoform dissociation as measured with the DSS and SDQ. Results The expected factorial structure of C-PTSD was replicated in the present sample, and the domains PTSD and disturbance in self-organization were found to be related but distinct constructs. All ICD-11 C-PTSD latent factors were associated with dissociative experiences. The strongest effects were found for the symptom clusters Affective Dysregulation, Disturbances in Relationship, and Re-Experiencing. However, dissociative Gaps in Awareness and Memory and Sensory Misperception were not predicted by any ICD-11 C-PTSD latent factors. Cumulative levels of dissociative experiences appeared to differentiate ICD-11 PTSD and C-PTSD with significantly higher levels for C-PTSD. Conclusion ICD-11 C-PTSD is strongly associated with dissociative phenomena in complex ways. Somatoform and psychoform manifestations of dissociation should be routinely assessed in patients with ICD-11 C-PTSD because such expressions may cover intense affects and painful relationship experiences. Future studies are needed to substantiate the causal and predictive relationship between ICD-11 C-PTSD and dissociation.
... Potential candidates enrolled themselves via an application integrated with a dedicated website, or were registered by healthcare providers and pastoral counselors. They filled in demographic information and completed online tests, including: Somatoform Dissociation Questionnaire (SDQ-20, Pietkiewicz et al., 2019a), Dissociative Experiences Scale -Revised (DESR, Pietkiewicz et al., 2019b), and Traumatic Experiences Checklist (Nijenhuis et al., 2002). They then participated in a semi-structured interview exploring their biography, family situation, religious socialization and spiritual involvement, and motives for enrolling in the study, followed by an in-depth clinical assessment investigating their symptoms. ...
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Article
The notion of evil spirits influencing human behaviour or mental processes is used in many cultures to justify various symptoms or experiences. It is also expressed in psychotic delusions of possession, but there is limited research in this area. This study explores how patients with schizophrenia came to the conclusion that they were possessed, and how this affected help-seeking. Interviews with two men and two women about their experiences and meaning-making were subjected to interpretative phenomenological analysis. Three main themes were identified: 1) Links between traumatic experiences and psychotic symptoms, 2) The emergence of religious themes in delusional contents, and 3) Reluctance to use medical treatment and instead to seek exorcism. In each case, attributing problems to possession was supported by the local environment and media, led to seeking spiritual help, and delayed diagnostic assessment and treatment. However, using religious coping contributed to the sense of predictability and social support. Clinicians are encouraged to explore the experiences and conflicts expressed by the symptoms which people ascribe to possession and to negotiate alternative explanatory models with their patients.
... Potential candidates enrolled themselves via an application integrated with a dedicated website, or were registered by healthcare providers and pastoral counsellors. They filled in demographic information and completed online tests, including: Somatoform Dissociation Questionnaire (Pietkiewicz, Hełka, & Tomalski, 2018), Dissociative Experiences Scale -Revised (Pietkiewicz, Hełka, & Tomalski, 2019), and Traumatic Experiences Checklist (Nijenhuis, Van der Hart, & Kruger, 2002). They then participated in a semi-structured interview exploring their biography, family situation, religious socialisation and spiritual involvement, and motives for enrolling in the study. ...
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There is a gap in research exploring the experiences and explanatory models of people labelled in local communities as possessed. While previous accounts often focused on the links between possession and dissociative disorders or psychosis, the current study elaborates on problems attributed to possession in women with features of personality disorders. Participants were eight Polish Roman Catholic women who had frequented deliverance ministries or individual exorcisms because they were perceived as suffering from malignant possession. Following clinical assessment, video-recorded in-depth interviews about possession experiences were transcribed and subjected to interpretative phenomenological analysis. Participants talked about: 1) Difficulties with expressing emotions and needs; 2) Aversion to the church and its people; 3) Casting spirits out; and 4) Negotiating explanatory models and seeking help. Data shows that the notion of possession can justify unaccepted conflicts and impulses associated with anger, sexuality, and attachment needs in women with personality disorders. Endorsement of, and identification with this belief can prevent people from taking ownership of emotions and using professional treatment. Alongside spiritual counselling, priests involved should have a basic understanding of mental disorders and encourage the use of clinical consultations.
... Test zawiera 20 pytań i 5-stopniową skalę odpowiedzi, umożliwiającą uzyskanie wyniku w przedziale 20-100 punktów, przez dodanie wartości poszczególnych itemów. Punkt odcięcia umożliwiający osiągnięcie maksymalnej czułości i swoistości narzędzia dla zaburzeń dysocjacyjnych (konwersyjnych) wynosi 29.5 (Pietkiewicz, Hełka, Tomalski, 2018b). ...
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The aim of this paper is to describe various forms of psychoform and somatoform dissociation, illustrating them with typical positive and negative symptoms. Different obstacles in identifying these symptoms during clinical assessment are also mentioned, including: insufficient training for psychiatrists, psychologists and psychotherapists about dissociation and trauma-related disorders, or patients’ phobic reactions and reluctance to discuss issues associated with traumatic experiences. Unclear diagnostic criteria and ambiguities related to psychiatric manuals are also discussed. Popular instruments utilised in the clinical assessment of dissociative symptoms, such as screening tools and structured interview protocols are also presented.
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Few studies on Possession Trance Disorder (PTD) describe diagnostic and research procedures in detail. This case study presents the clinical picture of a Caucasian Roman-Catholic woman who had been subjected to exorcisms because of her problems with affect regulation, lack of control over unaccepted sexual impulses, and somatoform symptoms accompanied by alterations in consciousness. It uses interpretative phenomenological analysis to explore meaning attributed by her to ‘possession’ as a folk category and a medical diagnosis; how this affected her help-seeking was also explored. This study shows that receiving a PTD diagnosis can reinforce patients’ beliefs about supernatural causation of symptoms and discourage professional treatment. Dilemmas and uncertainties about the diagnostic criteria and validity of this disorder are discussed.
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Background History of traumatic experience is common in dissociative disorder (DD), and similarity of symptoms and characteristics between DD and posttraumatic stress disorder (PTSD) encouraged to consider DD as trauma-related disorder. However, conceptualization of DD as a trauma-related syndrome would critically affect diagnosis and treatment strategies. The present study addressed overlap and disparity of DD and PTSD by directly comparing correspondence of symptoms, adverse/traumatic experience, and altered affect regulation between patients diagnosed with dissociative disorder (characterized by negative functional neurological symptoms) and patients diagnosed with PTSD. Methods Somatoform and psychoform dissociation, symptoms of posttraumatic stress, general childhood adversities and lifetime traumata, and alexithymia as index of altered affect regulation were screened with standardized questionnaires and semi-structured interviews in 60 patients with DD (ICD-codes F44.4, F44.6, F44.7), 39 patients with PTSD (ICD-code F43.1), and 40 healthy comparison participants (HC). Results DD and PTSD patients scored higher than HC on somatoform and psychoform dissociative symptom scales and alexithymia, and reported more childhood adversities and higher trauma load. PTSD patients reported higher symptom severity and more traumata than DD patients. Those 20 DD patients who met criteria of co-occuring PTSD did not differ from PTSD patients in the amount of reported symptoms of somatoform dissociation, physical and emotional childhood adversities and lifetime traumata, while emotional neglect/abuse in childhood distinguished DD patients with and without co-occuring PTSD (DD patients with co-occuring PTSD reporting more emotional maltreatment). Conclusion The pattern of distinctive somatoform and psychoform dissociative symptom severity, type of childhood and lifetime traumata, and amount of alexithymia suggests that DD and PTSD are distinctive syndromes and, therefore, challenges the conceptualization of DD as trauma-related disorder. Together with the detected close correspondence of symptom and experience profiles in DD patients with co-occuring PTSD and PTSD patients, these findings suggest that adverse/traumatic experience may intensify dissociative symptoms, but are not a necessary condition in the generation of functional neurological symptoms. Still, diagnosis and treatment of DD need to consider this impact of traumata and post-traumatic stress symptoms.
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Background: Somatoform dissociation is supposed to be a vital aspect of the general concept of dissociation. The Somatoform Dissociation Questionnaire-20 (SDQ-20) and the brief version SDQ-5 are self-report instruments constructed to identify somatic dissociation. Aim: In the present study, the psychometric qualities of the Swedish version of the SDQ-20 and its brief version, the SDQ-5, were examined among adolescents and young adults. Reliability and concurrent validity were investigated. Methods: A total of 512 adolescents and young adults participated in the study: 461 adolescents from a non-clinical sample and 50 adolescents and young adults from a clinical eating disorder outpatient unit. They completed the self-report instruments the SDQ-20, the SDQ-5 (part of SDQ-20), the Linköping Youth Life Experience Scale (LYLES, a trauma history scale) and the Dissociation Questionnaire-Sweden (Dis-Q-Sweden). Results: Both internal consistency and test-retest reliability of the Swedish version of SDQ-20 were good in both the non-clinical (α = 0.83) and the clinical groups (α = 0.84); the reliability for the SDQ-5 was, however, lower (non-clinical α = 0.50, clinical α = 0.64). Significant differences were found between the clinical and non-clinical groups on both somatoform and psychoform dissociation. Correlations between the Dis-Q-Sweden, SDQ-20 and SDQ-5 were generally high. The criterion and convergent validity was acceptable for both scales but somewhat better for SDQ-20 than for SDQ-5. Conclusion: The advantage with both the SDQ-20 and the SDQ-5 is that they are short questionnaires, but the results suggests that SDQ-20 is preferable based on the higher-quality psychometric properties of the SDQ-20.
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Objective: Somatoform dissociative phenomena have long existed in psychiatric nosology but few quantitative data exist. This study aims at substantiating the association between trauma and somatoform dissociation, and presenting elements of validation of the French version of the Somatoform Dissociation Questionnaire (SDQ-20). Indeed, the SDQ-20 is a simple to use self-report questionnaire developed to quantify somatoform dissociative symptoms.Methods: One hundred forty psychiatric outpatients consecutively seen in the University Hospital in Tours, France were included, and completed the SDQ-20, the Dissociative Experiences Scale (DES), an inventory of traumatic experiences, and underwent a structured interview (CAPS) for diagnosis of Posttraumatic Stress Disorder (PTSD) according to the DSM-IV criteria.Results: We found a strong association between the SDQ-20 mean score and current PTSD or past PTSD. The Principal Components Analysis of this French version yielded a solution containing three factors: sensory neglect, subjective reactions to perceptive distortions, and vigilance modulation disturbance. The reliability of this French version was studied through the Cronbach's α coefficient (0.83). Both scales of dissociation used in our study (DES, SDQ-20) were shown to be highly correlated.Conclusion: This study confirms the strong association between trauma and dissociative symptoms as a whole, including somatoform dissociation. The SDQ-20 appeared to be a potentially useful screening instrument for dissociative disorders. It shed light on a “sub-dimension” of the dissociative phenomenon, when expressed in a somatic way.
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Background: Childhood trauma is clearly associated with psychological dissociation a failure to integrate cognitive, behavioural and emotional aspects of experience. However, there is also evidence that trauma results in somatoform dissociation, where the individual fails to process somatic experiences adequately. Somatoform dissociation is linked to a number of psychiatric disorders that are relatively resistant to treatment. The present study addresses the hypothesis that somatoform dissociation will be associated specifically with childhood trauma that involves physical contact, rather than with non-contact forms of trauma. Methods: An unselected clinical group of 72 psychiatric patients completed standardized measures of childhood trauma, psychological dissociation, and somatoform dissociation. Results: The findings supported the hypothesis, with a specific link between somatoform dissociation and the severity of reported childhood trauma involving physical contact or injury. In contrast, psy...
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The objective of the study was to assess the reliability and validity of a retrospective self-report measure of potential traumatic experiences among psychiatric outpatients. The range of evaluated experiences includes emotional neglect and abuse. Participants completed the Traumatic Experiences Checklist (TEC) (N = 153), a self-report trauma questionnaire of known psychometric qualities, i.e. the Stressful Life Experiences Questionnaire (SLESQ), and self-report measures of somatoform dissociation (SDQ-20), psychoform dissociation (DES). A majority (N = 115) completed the TEC twice, and also completed a measure of posttraumatic stress symptoms (PTSD-ss). The TEC's internal consistency and test–retest reliability were good, and the TEC strongly correlated with the SLESQ. Associations between the TEC and the PTSD-ss, DES, and SDQ-20 supported the criterion-related validity of the TEC. The internal consistency, test–retest reliability and criterion-related validity of TEC trauma area presence and severity scores were also satisfactory. Preliminary findings suggest that the psychometric characteristics of the TEC are good. Future study of the TEC should include larger samples of psychiatric patients, as well as non-clinical groups. Copyright © 2002 John Wiley & Sons, Ltd.
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Using cases of dissociative disorder (n=50) and other DSM-IV diagnoses (n=50), a somatoform dissociation self-report questionnaire was developed and its capacity to function as a screening device for dissociative disorders was analysed. A list of 75 items was constructed which, according to clinical experience and expert judgement, could reflect instances of somatoform dissociation. Statistical analyses revealed the 20 best discriminating items. Stepwise forward logistic analysis detected five items which, as a group, provided optimal discrimination between the two groups. At an estimated prevalence rate of dissociative disorders of 10% among psychiatric patients the sensitivity would be 94%, the specificity would be 96%, the positive predictive value would be 72%, and the negative predictive value would be 99%. Cross-validation in an independent sample (n=33/42) largely corroborated the initial findings. The SDQ-5 can be used as a brief screening device for dissociative disorders.
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The present study aimed to replicate the results of previous studies concerning the development of two versions of the Somatoform Dissociation Questionnaire. The SDQ-20 evaluates the severity of somatoform dissociative phenomena, and the SDQ-5 is a dissociative disorders screening instrument. Thirty-one patients with dissociative disorders and 45 consecutive psychiatric outpatients with other DSM-IV diagnoses completed the SDQ-20 and SDQ-5 as well as the Dissociation Questionnaire which measures psychological dissociation. Mokken scale analysis showed that the items of the SDQ-20 are strongly scalable on a latent unidimensional scale. Internal consistency was high. The SDQ-20 convergent validity was supported by high intercorrelations with the DIS-Q. Dissociative patients obtained significantly higher scores than comparison patients. Patients with dissociative identity disorder scored significantly higher compared to patients with dissociative disorder nos. Sensitivity (94%) and specificity (98%) of the SDQ-5 were very satisfactory, as were, at an estimated prevalence rate of dissociative disorders of 10% among psychiatric patients, positive predictive value (84%) and negative predictive value (99%). All results replicated the first findings, and therefore corroborate the conclusion that the SDQ-20 and SDQ-5 are instruments of sound psychometric quality, and that somatoform dissociative phenomena are core symptoms of complex dissociative disorders.
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The primary aim of this study was to investigate the hypothesis that somatoform dissociation would differentiate among specific diagnostic categories after controlling for general psychopathology. The Somatoform Dissociation Questionnaire (SDQ-20), the Dissociative Experiences Scale, and the Symptom Checklist-90-R were completed by patients with DSM-IV diagnoses of dissociative disorders (n = 44), somatoform disorders (n = 47), eating disorders (n = 50), bipolar mood disorder (n = 23), and a group of consecutive psychiatric outpatients with other psychiatric disorders (n = 45), mainly including anxiety disorders, depression, and adjustment disorder. The SDQ-20 significantly differentiated among diagnostic groups in the hypothesised order of increasing somatoform dissociation, both before and after statistically controlling for general psychopathology. Somatoform dissociation was extreme in dissociative identity disorder, high in dissociative disorder, not otherwise specified, and increased in somatoform disorders, as well as in a subgroup of patients with eating disorders. In contrast with somatoform dissociation, psychological dissociation did not discriminate between bipolar mood disorder and somatoform disorders. Somatoform dissociation is a unique construct that discriminates among diagnostic categories. It is highly characteristic of dissociative disorder patients, a core feature in many patients with somatoform disorders, and an important symptom cluster in a subgroup of patients with eating disorders.
Article
Background: The Somatoform Dissociation Questionnaire (SDQ-20) is a self-reported questionnaire measuring somatoform dissociation. The aim of this study is to analyze the psychometric properties of the Spanish version of the SDQ-20 and its short version (SDQ-5). Methods: Validity and reliability were examined in a sample of 360 psychiatric outpatients: 38 dissociative (conversion) disorders, 30 dissociative (psychoform) disorders, and 292 patients suffering from other disorders. Dissociative disorders were diagnosed using the SCID-D and a specific interview for conversion disorders. Results: Subjects meeting criteria for any dissociative or conversion disorder scored significantly higher in the SDQ-20 (criterion validity). Somatoform dissociation, psychoform dissociation and early trauma were significantly correlated (construct validity). An alpha coefficient of .866 (reliability) and a test-retest correlation of 0.91 were obtained. The cut-off score maximizing sensitivity and specificity was 27.5 for psychoform dissociative disorders (sensitivity of 81.6% and specificity of 71.0%) and 29.5 for conversion disorders (81.6% and 71.0%). For the SDQ-5, the coefficient alpha was 0.561 and the selected cut-off score was 5.5 (sensitivity of 73.33% and specificity of 70.41%). Conclusions: The Spanish version of the SDQ-20 presents good psychometric properties while the SDQ-5 shows worse characteristics and its use with Spanish samples is not recommended.
Article
This study aimed to assess the reliability, validity, and psychometric characteristics of the Turkish version of the Somatoform Dissociation Questionnaire (SDQ-20). In this context, it investigated whether somatoform dissociation differentiates dissociative disorders from other diagnostic groups and non-clinical individuals. The Turkish Version of the SDQ-20 was administered to 50 patients with a dissociative disorder, 94 patients with psychiatric disorders other than dissociative disorder, and 175 non-clinical participants. To confirm the clinical diagnosis, all patients in the dissociative disorder group had been evaluated using the Structured Clinical Interview for DSM-IV Dissociative Disorders. The internal consistency and the tcst-retcst correlation of the SDQ-20 were excellent. The scale had strong correlations with the DES and the DIS-Q. There was a statistically significant difference between dissociative patients and other diagnostic groups on the SDQ-20 total score. The discriminative power of the SDQ-20 was as robust as that of the DES. There was no significant difference between the mean SDQ-20 total scores of Turkish and Dutch patients, but Turkish dissociative patients reported pseudoseizures more frequently than Dutch patients. The specificity of the short version of the scale (SDQ-5) was weak among Turkish patients. Dissociative disorders can be differentiated from other diagnostic groups through somatoform dissociation. The good psychometric characteristics of the SDQ-20 among Turkish par-ticipants support its cross-cultural validity.
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Objective: This review aims to address concerns about the potential overinclusiveness and vagueness of bipolar spectrum concepts, and also, concerns about the overlap between bipolar illness and borderline personality. Method: Narrative review based on historical and empirical studies. Results: Bipolar disorder (BD) and major depressive disorder (MDD) came to be separate entities with the Diagnostic and Statistical Manual of Mental Disorders, Third Edition (DSM III), in contrast to the Kraepelinian manic-depressive insanity (MDI) concept, which included both. The bipolar spectrum concept is a return to this earlier Kraepelinian perspective. Further, very different features differentiate the disease of bipolar illness (family history of bipolar illness, severe recurrent mood episodes with psychomotor activation) from the clinical picture of borderline personality (dissociative symptoms, sexual trauma, parasuicidal self-harm). The term 'disorder' obfuscates an ontological difference between diseases, such as manic-depressive illness, and clinical pictures, such as hysteria/post-traumatic stress disorder/dissociation/borderline personality. Conclusions: Bipolar spectrum concepts are historically rooted in Kraepelin's manic-depressive illness concept, are scientifically testable, and can be clearly formulated. Further, they differ in kind from traumatic/dissociative conditions in ways that can be both historically and scientifically established.
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In most of the recent scientific and clinical literature, dissociation has been equated with dissociative amnesia, depersonaliza- tion, derealization, and fragmentation of identity. However, according to Pierre Janet and several World War I psychiatrists, dissociation also pertains to a lack of integration of somatoform components of experi- ence, reactions, and functions. Some clinical observations and contem- porary studies have supported this view. Somatoform dissociation, which can be measured with the Somatoform Dissociation Questionnaire (SDQ-20), is highly characteristic of dissociative disorder patients, and a core feature in many patients with somatoform disorders and in a subgroup of patients with eating disorders. It is strongly associated with reported trauma among psychiatric patients and patients with chronic pelvic pain presenting in medical healthcare settings. Motor inhibitions and anesthesia/analgesia are somatoform dissociative symptoms that are similar to animal defensive reactions to major threat and injury. Among a wider range of somatoform dissociative symptoms, these particular symptoms are highly characteristic of patients with dissocia- tive disorders. The empirical findings reviewed in this article should have implications for the contemporary conceptualization and defini- tion of dissociation, as well as the categorization of somatoform disor- ders in a future version of the DSM. (Article copies available for a fee from The Haworth Document Delivery Service: 1-800-342-9678. E-mail address: Website:
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An attempt is made to explicate the meaning of construct validity. Operational issues in the process of construct validation are investigated. A subset of "JMR" studies involving construct validation are reviewed and the role of construct validity in marketing is considered.
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Reviews a new diagnostic tool, the SCID-D, which comprehensively evaluates the severity of 5 posttraumatic dissociative symptoms (amnesia, depersonalization, derealization, identity confusion, identity alteration) and the dissociative disorders. Several investigations have reported good-to-excellent reliability and validity of the SCID-D. The clinical assessment of dissociative symptoms, as well as the diagnosis of dissociative disorders using the SCID-D, based on research at Yale University involving over 400 interviews over a 10-yr time period is described. (PsycINFO Database Record (c) 2012 APA, all rights reserved)
Article
The present study investigated the validity of the German version of the Somatoform Dissociation Questionnaire (SDQ-20), a scale designed to measure somatoform dissociative symptoms. Somatoform dissociation involves physical manifestations of a dissociation of the personality and is considered a unique entity in the phenomenological spectrum of dissociation. The validity and reliability of the German version of the SDQ-20 was examined using a sample of 225 patients with (n = 39) and without dissociative disorders who were recruited from several in- and outpatient psychiatric clinics. Patients were assessed using structured diagnostic interviews; diagnostic checklists; and self-rating scales for dissociation, and posttraumatic stress. Patients with dissociative disorders reported significantly more (p < .001) somatoform dissociative symptoms than patients without dissociative disorders (criterion validity). Significant correlations (p < .001) were found between scores of somatoform dissociation, psychoform dissociation, posttraumatic stress symptoms, and traumatic childhood experiences (construct validity). Reliability was corroborated by a Cronbach's alpha coefficient of .91 and a test-retest correlation of .89. A component factor analysis suggested unidimensionality of the SDQ-20. In conclusion, the psychometric properties and cross-cultural validity of the German version of the SDQ-20 are excellent. Our results form the basis for the further study of somatoform dissociation in German-speaking populations.
Article
This study investigates somatoform as well as psychological dissociation, somatization and reported trauma among patients with chronic pelvic pain (CPP). Women with CPP (n = 52) who were newly referred to a gynecology department, or whose pain had resisted treatment, completed standardized self-report questionnaires and received a structured interview for DSM-IV dissociative disorders. The prevalence of dissociative disorders in the sample was very low. As hypothesized, self-reported somatoform dissociation was positively correlated with self-reported psychological dissociation and features of DSM-IV dissociative disorders; women who reported more serious psychic trauma, in particular sexual and physical abuse, experienced more somatoform and psychological dissociation than women reporting less trauma, or no trauma at all; and the association of somatoform dissociation and reported trauma was stronger than the association of psychological dissociation and trauma. Physical abuse/life threat posed by a person predicted somatoform dissociation best. The results are consistent with findings among psychiatric patients, and, therefore, strengthen the thesis that somatoform dissociation, (features of) dissociative disorder, and reported trauma are strongly intercorrelated phenomena.
Article
We assessed psychological and somatoform dissociation and their relationships in the general population. The study questionnaires included the Dissociative Experiences Scale, the Somatoform Dissociation Questionnaire, the Beck Depression Inventory, and background characteristics. Four study groups were formed: subjects with low dissociation scores (N = 1334), with high psychological dissociation (N = 93), with high somatoform dissociation (N = 93), and with high psychological and somatoform dissociation (N = 65). Those with high psychological and somatoform dissociation differed clearly from the other groups. They had depressive symptoms, suicidal ideation, a reduced working ability, a poor financial situation, poor general health, and inadequate social support more frequently than subjects in the other groups. Thus, a considerable amount of ill health was recorded in this group.
Trauma and dissociation symptoms interview (TADS-I), version 1
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Dissociative disorders and other psychopathological groups: exploring the differences through the Somatoform Dissociation Questionnaire (SDQ-20)
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