Self-Reported Personality Pathology Has Complex Structure and Imposing Simple Structure Degrades Test Information.

Area of Science:

• Psychometrics
• Personality Psychology
• Quantitative Psychology

Background:

• Simple structure is a theoretical guideline for exploratory factor analysis rotations.
• Its empirical validation in personality pathology inventories is often overlooked.
• Multivariate complexity is a key consideration in factor analysis.

Purpose of the Study:

• To empirically assess the degree of simple structure in two personality pathology inventories.
• To compare the complexity of these inventories against simulated simple structure solutions.
• To evaluate the impact of imposing simple structure on test information.

Main Methods:

• Exploratory factor analysis was applied to two self-report personality pathology inventories.
• Multivariate complexity was compared to simulated factorial solutions with varying simple structure degrees.
• Multidimensional item response theory (IRT) test information functions were analyzed.

Main Results:

• Both inventories exhibited high multivariate complexity, irrespective of factor breadth or analysis unit (items/scales).
• Thurstone's simple structure criteria were seldom fulfilled in these personality pathology solutions.
• Imposing simple structure reduced test information accuracy in interstitial areas.

Conclusions:

• Simple structure criteria are rarely met in multivariate personality pathology, supporting the use of alternate rotations.
• Complex solutions provide more uniform test information distribution compared to imposed simple structure.
• The findings have implications for test development and the interpretation of personality pathology measures.