Abnormalities in biological rhythms (BR) may have a role in the pathophysiology of Bipolar Disorders (BD). The objective of this study is to validate the Italian version of the Biological Rhythms Interview of Assessment in Neuropsychiatry (BRIAN), a useful tool in studying BR, and measure its accuracy in discriminating BD.
44 outpatients with DSM-IV-TR diagnosis of BD and 38 controls balanced for sex and age were consecutively recruited. The discriminant validity of BRIAN for the screening of BD and its test re-test reliability in two evaluations were assessed.
BD patients scored 22.22±11.19 in BRIAN against 7.13±5.6 of the control group (P<0.0001). BRIAN showed a good accuracy to screen between BD non-BD at cutoff 16, a sensitivity was 68.2 and specificity was 92.5. The test-retest stability measured using Pearson’s coefficient found very high r values for each section and the total score, thus indicating a correlation at the two times of statistical significance in all measures. Cohen’s Kappa varied from 0.47 in the sociality section to 0.80 in the sleep section, with a total K mean of 0.65.
The results show that the Italian version of BRIAN has good discriminant validity in detecting BD from healthy controls and shows good test-retest reliability. The study suggests the possibility of developing mixed screening tools by introducing items on dysregulation of biological rhythms to the usual measures of mood.