1244 – Bipolar depression rating scale (BDRS): psychometric characteristics of the italian validation

Introduction The scales for the assessment of depressive symptoms, translated and validated in Italian, lacks in the recognition of the psychopathological nuances of the disorder. The Bipolar Depression Rating Scale (BDRS) is a tool specifically built to reflect the characteristics of bipolar depression. Methods Screening criteria: -aged 18–65 years -diagnosis of BD (DSM-IV-TR) (125 patients) or -diagnosis of MDD (DSM-IV-TR) (30 patients) -manifestation of depressive symptoms -no further psychiatric comorbidity on axis I and axis II (including abuse/addiction) -no serious cognitive deficits Psychometric battery: Bipolar Depression Rating Scale (BDRS), Hamilton Depression Rating Scale (HAM-D), Montgomery-Asberg Depression Rating Scale (MADRS), Young Mania Rating Scale (YMRS). Results The analysis of the BDRS scores, according to the Kolmogorov-Smimov method shows a normal distribution; the α Cronbach's coefficient shows that the the scale, in its Italian version, has considerable validity and reliability (r=0.82). The factor analysis was verified using the Varimax rotational method: after several tests, we found 2 subscales, one linked to mixed/depressive symptoms and a second related to (hypo)manic symptoms. Conclusions The BDRS is a valid scale for the measurement of depression in patients with Bipolar Disorder, with a notable internal consistency (Cronbach α 0.82), a significant consistency between items/total (Cronbach α from 0.80 to 0.82) and positive correlation with other scales (MADRS r 0.67, p