Transcultural adaption and validation of the Spanish version of the Bipolar Depression Rating Scale (BDRS-S)

Background: The Bipolar Depression Rating Scale (BDRS) arguably better captures symptoms in bipolar depression especially depressive mixed states than traditional unipolar depression rating scales. The psychometric properties of the Spanish adapted version. BDRS-S, are reported. Methods: The BDRS was translated into Spanish by two independent psychiatrists fluent in English and Spanish. After its back-translation into English, the BDRS-S was administered to 69 DSMI4V bipolar l and II patients who were recruited from two Spanish psychiatric hospitals. The Hamilton Depression Rating Scale (HDRS), the Montgomery-Asberg Depression Rating Scale (MADRS) and the Young Mania Rating Scale (YMRS) were concurrently administered. 42 patients were reviewed via video by four psychiatrists blind to the psychopathological status of those patients. In order to assess the BDRS-S intra-rater or testretest validity, 22 subjects were assessed by the same investigator performing two evaluations within five days. Results: The BDRS-S had a good internal consistency (Cronbach's (alpha=0.870). We observed strong correlations between the BDRS-S and the HDRS (r=0,874) and MADRS (r=0,854) and also between the mixed symptom cluster score of the BDRS-S and the YMRS (r =0.803). Exploratory factor analysis revealed a three factor solution: psychological depressive symptoms cluster, somatic depressive symptoms cluster and mixed symptoms cluster Limitations: A relatively small sample size for a 20-item scale. Conclusions: The BDRS-S provides solid psychometric performance and in particular captures depressive or mixed symptoms in Spanish bipolar patients. (C)2014 Elsevier B.V. All rights reserved