Study of the Brief Personality Scale (BPS) from the Classical Theory of Test and the Item Response Theory

Abstract

This study presents a psychometric analysis of a Brief Personality Scale from the Classical Test Theory (CTT) and the Item Response Theory (IRT). A probabilistic sample of 1,284 people between 18 and 65 years was taken from the cities of Córdoba, Salta and Neuquén (AR). Confirmatory factor analysis evidenced adequate global adjustments for a five-factor model. The internal consistency analysis showed adequate indices. The results from the IRT approach evidenced that most of the items fit adequately to the continuous response model, and the parameters suggest that the estimation of a wide range of latent trait values discriminate between people with different trait levels. The correlations between the statistics obtain from a TCT and IRT approach were high. Overall, the EBP is a short, useful, and reliable instrument for the study of personality.