Clinical validation of the BDS_x scale with bipolar disorder outpatients

Purpose: The BDS_x (Bipolar Disorder Symptom Scale) is a brief self-report instrument designed for repeated measurement of bipolar disorder (BD) symptoms over time. Previous research indicates that the BDS_x measures two depression (cognitive and somatic symptoms) and two hypo/mania factors (affrontive symptoms and elation/loss of insight). The purpose of this study was to validate BDS_x responses relative to diagnoses of BD mood episodes. Methods: Sixty BD outpatients attending routine clinic appointments completed the BDS_x, the Hamilton Rating Scale for Depression, the Altman Self-Rating Mania Scale, and the Satisfaction with Life Scale. Blind to scale responses by patients, a clinic psychiatrist determined if patients were currently symptomatic. Results: BDS_x depression and hypo/mania subscales showed good construct validity vis-à-vis clinical diagnoses, and concurrent/discriminant validity with other self-report scales. And though not designed as a screening measure, sensitivity for the depression subscale is high at 88% (6+, 76% specificity), yet lower at 57% for the hypo/mania subscale (5+, 90% specificity). Conclusions: The results of this study indicate that BDS_x responses distinguish patients experiencing depressive and hypo/manic mood episodes. Findings support the psychometric properties of the Hebrew version of this scale. The BDS_x enables those with bipolar disorder to monitor their symptoms, gauge symptom variability, and identify factors that proceed and sustain BD symptoms over time.