Validity and reliability of the Spanish version of the Somatoform Dissociation Questionnaire

• Published in: Psicothema Vol. 29; no. 2; p. 275
• Main Authors: Gonzalez-Vazquez, Ana Isabel, del Rio-Casanova, Lucia, Seijo-Ameneiros, Natalia, Cabaleiro-Fernandez, Paloma, Seoane-Pillado, Teresa, Justo-Alonso, Ania, Santed-German, Miguel Angel
• Format: Journal Article
• Language: Spanish
• Published: Colegio Oficial De Psicologos Del Principado De Asturias 01.04.2017
• Subjects: Estados Unidos
• ISSN: 0214-9915; 1886-144X
• DOI: 10.7334/psicothema2016.346

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 SDQ20 (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. Keywords: Conversion disorders, dissociative disorders, stress disorders, post-traumatic, validation study. Antecedentes: SDQ-20 (Somatoform Dissociation Questionnaire) es un autoinforme que mide la presencia de disociacion somatomorfa. Se analizan las propiedades psicometricas de la version espanola de la SDQ-20 y su version abreviada (SDQ-5). Metodo: su validez y fiabilidad han sido examinadas en una muestra de 360 pacientes: 38 trastorno disociativo (de conversion), 30 trastorno disociativo (psicomorfo) y 292 diagnosticados de otros trastornos. El diagnostico de trastorno disociativo se realizo mediante la SCID-D-TR y una entrevista especifica para los trastornos conversivos. Resultados: los sujetos que cumplieron criterios de trastorno disociativo o conversivo puntuaron significativamente mas alto en la SDQ-20 (criterio de validez). La disociacion psicomorfa y somatomorfa y el trauma temprano se correlacionaron significativamente (validez del constructo). Se obtuvieron un coeficiente alpha de 0.866 (fiabilidad) y una correlacion test-retest de 0,91. El punto de corte para los trastornos disociativos fue 27,5 (sensibilidad 81,6% y especificidad 71%) y 29,5 para los trastornos conversivos (81,6% y 71%). En la SDQ-5 se obtuvo un coeficiente alpha de 0,561 y un punto de corte de 5,5 (sensibilidad 73,33% y especificidad 70,41%). Conclusiones: la version espanola de la SDQ-20 presenta buenas propiedades psicometricas. La SDQ-5 muestra peores caracteristicas y su uso en muestras espanolas no se recomienda. Palabras clave: trastorno conversivo, trastorno disociativo, trastorno por estres postraumatico, estudio de validacion.