Introduction: Unlike unipolar depression, depressive episode of bipolar disorder is often associated with clinical characteristics, such as atypical and mixed symptoms. However, there are currently no valid and reliable specific tools available to assess the specific psychiatric symptomatology of depressive episode of bipolar disorder in China. Therefore, we aimed to evaluate the psychometric properties of the Chinese version of the Bipolar Depression Rating Scale (BDRS) in Chinese patients with bipolar disorder.
Methods: The sample of this study included 111 patients with bipolar disorder (30 male, 81 female). All participants were interviewed with the Chinese version of the BDRS (BDRS-C), the 17-item Hamilton Depression Rating Scale (HAMD-17), the Montgomery-Asberg Depression Rating Scale (MADRS) and the Young Mania Rating Scale (YMRS). A psychometric analysis of the BDRS was conducted.
Results: The Cronbach’s alpha coefficient of the BDRS-C reached a value of 0.869. The BDRS-C score and scores for the HAMD-17 (r = 0.819, p < 0.01), the MADRS (r = 0.882, p < 0.01) and the YMRS (r = 0.355, p < 0.01) exhibited significant positive correlations. Close correlations were observed between the mixed subscale score of the BDRS-C and the YMRS score (r = 0.784, p < 0.01). Exploratory factor analysis resulted in three factors: a primary depressive symptoms cluster, a secondary depressive symptoms cluster, and a mixed symptoms cluster.
Conclusion: The Chinese version of the BDRS has satisfactory psychometric properties. This is a valid and reliable instrument to assess depressive symptomatology in patients with bipolar disorder.
Keywords: bipolar disorder, mania, depression, psychometrics, depressive episode, rating scale, psychiatry