An openness scale for the California Psychological Inventory

Area of Science:

• Psychological Measurement
• Personality Psychology
• Industrial-Organizational Psychology

Background:

• The California Psychological Inventory (CPI) is a widely used personality assessment tool.
• Measuring the personality trait of Openness is crucial in various psychological and organizational contexts.
• Existing scales may have limitations in measuring Openness, necessitating new instrument development.

Purpose of the Study:

• To develop and validate a new 36-item scale to measure Openness.
• To assess the reliability, construct validity, and predictive validity of the new Openness scale.
• To establish norms for the scale in university undergraduate and nonmanagement call center job applicant populations.

Main Methods:

• Development of a 36-item Openness scale using items from the California Psychological Inventory (CPI).
• Data collection from five samples (N = 2,375) including university undergraduates and call center job applicants.
• Reliability (internal consistency, test-retest) and validity (construct, predictive) analyses were conducted, alongside norm development.

Main Results:

• The new Openness scale demonstrated good internal consistency (average alpha ≈ .75) and high test-retest stability (r = .84).
• Evidence for construct validity was supported by cross-correlations with established Openness measures (e.g., NEO-PI-R).
• The scale showed statistically significant predictive validity for job performance criteria in call center roles (true validities .20–.36).

Conclusions:

• The developed 36-item CPI-based Openness scale is a reliable and valid measure.
• The scale possesses significant predictive utility for job performance, particularly in service sector roles.
• Norms are available for university students and nonmanagement service-sector job applicants, enhancing its practical application.