Calibrating a new item pool to adaptively assess the Big Five

Area of Science:

• Psychometrics
• Personality Psychology
• Psychological Measurement

Background:

• The Five Factor Model (FFM) is a dominant personality theory.
• Adaptive measurement of the FFM is underrepresented in research.
• A need exists for efficient FFM assessment tools.

Purpose of the Study:

• To develop a new item pool for a computerized adaptive test (CAT) of the FFM.
• To create a more efficient method for personality assessment.

Main Methods:

• Developed a 480-item pool measuring FFM facets.
• Administered the pool to 826 participants.
• Calibrated facets individually, ensuring unidimensionality.
• Conducted a post-hoc simulation study for CAT performance evaluation.

Main Results:

• A final 360-item pool with strong psychometric properties was created.
• A 120-item CAT (4 items per facet) accurately measured FFM facets.
• The CAT maintained the FFM's factor structure.

Conclusions:

• A psychometrically sound item pool for FFM CAT was developed.
• CAT simulations confirmed precise measurement of FFM facets with reduced item count.