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Somatoform Dissociation Questionnaire - 20 (SDQ-20)

Title of the Portuguese Version

Questionário da Dissociação Somatoforme

Original Version

Nijenhuis, E., Spinhoven, P., Van Dyck, R., Van der Hart, O., & Vanderlinden, J. (1996)

Portuguese Version

Espírito-Santo, H., & Pio Abreu, J. L. (2007)

General Description

CHARACTERIZATION: SDQ is a 20-item self-response questionnaire that measures the intensity of somatoform dissociation. STRUCTURE AND SCORING: The items are answered with a Likert-type 5-point scale. The range of scores is 20 – 100 (high dissociation). PSICOMETRIC CHARACTERISTICS: Adequate corrected item-total correlations (varying between r = 0.31 and r = 0.63). Internal consistency, measured by Cronbach’s alpha was 0.94. CUTOFF SCORE and DIAGNOSTIC ACCURACY: The best sensitivity-specificity relation of the SDQ-20 was established at a cut-off point of 35. The sensitivity rate was 0.73, the specificity rate was 0.66, positive predictive value was 0.54, and negative predictive value was 0.21.

  • Espirito-Santo, H., & Pio Abreu, J. L. (2007). Dissociative disorders and other psychopathological groups: exploring the differences through the Somatoform Dissociation Questionnaire (SDQ-20). Revista Brasileira de Psiquiatria, 29, 354-358. doi:10.1590/S1516-44462006005000039

  • Nijenhuis, E. R. S., Spinhoven, P., Van Dyck, R., Van der Hart, O., & Vanderlinden, J. (1996). The development and the psychometric characteristics of the Somatoform Dissociation Questionnaire (SDQ-20). Journal of Nervous and Mental Disease, 184, 688-694. doi:10.1159/000012254