A Bifactor Model of Personality Organization

Area of Science:

• Psychology
• Psychopathology
• Personality Assessment

Background:

• The Inventory of Personality Organization (IPO) measures personality functioning based on Kernberg's model.
• Exploring the factor structure of the IPO is crucial for understanding personality organization.

Purpose of the Study:

• To investigate the viability of a bifactor model for the German 83-item version of the IPO.
• To assess the general and specific factors of personality organization within Kernberg's framework.
• To develop a brief form of the IPO based on the bifactor model.

Main Methods:

• Confirmatory and Exploratory Factor Analyses were used on a sample of 616 participants.
• The factor structure of the 83-item German IPO was examined.
• Convergent and discriminant validity were assessed against interview-based measures.

Main Results:

• A bifactor model was successfully established, comprising a general factor of personality functioning and three specific factors: Aggression, Reality Testing, and Moral Values.
• The general factor accounted for approximately 66% of the common variance.
• The general and specific factors demonstrated convergent and discriminant validity.

Conclusions:

• The findings support a bifactor approach to Kernberg's model of personality organization.
• A 30-item brief form of the IPO, reflecting the bifactor structure, was developed and may be useful for future research and clinical application.