Reliability and Validity Study of the Turkish Version of Bipolar Spectrum Diagnostic Scale

Abstract

The purpose of this study is to evaluate the reliability and validity of the Turkish Version of the Bipolar Spectrum Diagnostic Scale (BSDS). The study was carried out with 130 patients diagnosed with bipolar I disorder, 15 patients diagnosed with bipolar II disorder, and 38 patients diagnosed with major depressive disorder attending the outpatient psychiatry departments of the Bakırköy Prof. Dr. Mazhar Osman Training and Research Hospital for Mental Health and Neurological Diseases. The Mood Disorder Questionnaire (MDQ) was used for convergent validity. The internal consistency coefficient, itemtotal score correlation coefficients, test-retest correlation coefficient, confirmatory factor analysis, correlation with concurrent scale, and ROC curve were statistically calculated. Confirmatory factor analysis indicated that the 20-item version did not show adequate goodness-of-fit. The item 4 with a relatively low regression weight was removed from the model. For the 19-item revised and corrected model, the observed goodness-of-fit indexes were RMSEA = 0.040, CFI = 0.900, GFI = 0.890, IFI = 0.900 and χ2/df = 1.230. The internal consistency Cronbach's alpha coefficient was 0.831. The correlation coefficient between the Turkish version of the BSDS and the MDQ was 0.54. The cutoff point of the scale calculated by the ROC analysis was 12 with a sensitivity of 78.6% and a specificity of 86.8%. The Turkish Version of the BSDS, has been shown to be reliable and valid tool for screening bipolar disorder after removal of the item 4 of the original version of the scale.