The Trier Integrated Personality Inventory. Development of the instrument and comparative psychometric analyses according to the ordinal Rasch model and classical test theory

The Trier Integrated Personality Inventory (TIPI version 4) is constructed according to the one-dimensional ordinal Rasch model and provides measurements of "normal" and "disordered" personality. It contains 34 scales with 254 items. The development of the instrument as well as comparative psychometric analyses according to the Rasch model and classical test theory within the standardization sample (1026 subjects) are reported. All scales meet the high demands of the Rasch model. Person parameters correlate very highly with the sum scores; however, the latter provide distorted measure-menu in the upper and lower part of the distribution. A factor analysis shows that four major factors ("Big Four") underlie the TIPI: Neuroticism vs. Mental Health, Extraversion/Openness, Conscientiousness/Control, and Disagreeableness vs. Agreeableness. It is concluded that it is possible and advantageous to construct personality questionnaires according to the Rasch model.