UC Berkeley

The aim of this study was to develop and validate manic and depressive scales carved from the full-length General Behavior Inventory (GBI). The brief version was designed to be applicable for youths and adults and to improve separation between mania and depression dimensions. Data came from 9 studies (2 youth clinical samples, aggregate N = 738, and 7 nonclinical adult samples, aggregate N = 1,756). Items with high factor loadings on the 2 extracted dimensions of mania and depression were identified from both data sets, and final item selection was based on internal reliability criteria. Confirmatory factor analyses described the 2-factor model's fit. Criterion validity was compared between mania and depression scales, and with the full-length GBI scales. For both mania and depression factors, 7 items produced a psychometrically adequate measure applicable across both aggregate samples. Internal reliability of the Mania scale was .81 (youth) and .83 (adult) and for Depression was .93 (youth) and .95 (adult). By design, the brief scales were less strongly correlated with each other than were the original GBI scales. Construct validity of the new instrument was supported in observed discriminant and convergent relationships with external correlates and discrimination of diagnostic groups. The new brief GBI, the 7 Up 7 Down Inventory, demonstrates sound psychometric properties across a wide age range, showing expected relationships with external correlates. The new instrument provides a clearer separation of manic and depressive tendencies than the original. (PsycINFO Database Record (c) 2013 APA, all rights reserved).