Validation and Development of Interpretation Norms to the Personality Disorders Dimensional Inventory

Abstract

The personality theory of Theodore Millon is distinguished by being a integrative model, that considers the healthy and patologic personality manifestations in several domains and in the relation with enviroment. In this teoric model, the personality disorders can be understood as personality styles that exhibit consistently non-adaptatives reactions in the social sistem in which the individual inhabit. Despite of the importance of evaluate and diagnose the personality disorders, in Brazil, tests in that area are scarce. Before that, in the Psychologic and Educacional Assessment Laboratory (PEALab), was developed the Personality Disorders Dimensional Inventory (PDDI), as well as was gathered data with intention of verifying the psychometric properties of this instrument. Although, besides investigation of psychometric properties commonly examined, validity and reliability, literatury indicate to the relevance of development of interpretation scales of instruments scores. The present study´s objective is to apply modern psychometrics procedures to improve the interpretation of IDTP scales, as well as continue searching for this instrument´s validity evidences and reliability. Participants were 400 undergraduated and 100 patient with psychiatric diagnoses. Statistics procedures were utilized based in Item Response Theory (IRT), to the development of interpretation scale of IDTP scores with reference to the norm, criterion and item; exploratory and confirmatory factorial analysis to verify validity evidences based on the internal structure; structural equation modeling to verify validity evidences based on the relation with external variables; and, Cronbach´s coeficient to verify the reliability of instrument factors.