This research responds to one phase of the process for the design and standarization of the MSAD Multidimentional Scale of Affective Disorders -EMTA in Spanish-, whose purpose was to analyze MSAD, from the Classical Test Theory (CTT) and the Item Response Theory (TRI), from a sample of 384 students enrolled to three universities in Barranquilla, aged between 17 and 26 years. This is considered an instrumental study, due to its purpose. The data were collected through he administration of three instruments: Scale Multidimensional Affective Disorder, The Beck Depression Inventory (α= .791) and the self-administered Altman Scale (α= .566). Finally, results were reported as adjusted to the parameters of both models. Analysis from the TCT showed high Cronbach alpha indexes for both subscales (α= .942 for the Depression Subscale and α = .864 for the Subscale Mania), as well as high internal item-scale correlations above .3 for all items. Since the TRI, reliability in the case of Depression .88 (individuals) and .99 (items) were reported, while rates regarding Mania were .84 (persons) and .87 (items). Results retained an increasing monotonic confguration; thus the principle of invariance in measuring the latent trait is corroborated. keywords Affective disorders; Item response theory; Multidimensional scale of affective disorders; Test classical theory