Measuring single constructs by single items: Constructing an even shorter version of the "Short Five" personality...

Area of Science:

• Psychological Measurement
• Personality Psychology

Background:

• Established personality inventories like NEO PI-R are lengthy.
• There is a need for shorter, yet psychometrically sound, personality assessments.

Purpose of the Study:

• To develop a brief, 30-item personality questionnaire (XS5) comparable to longer, established inventories.
• To optimize item selection for content and score meaning within the five-factor model framework.

Main Methods:

• Shortened the 60-item "Short Five" (S5) questionnaire by half, selecting one item per domain.
• Compared item selection possibilities based on correlations with established scales, self-peer correlations, and clarity.
• Validated the resulting XS5 against the original S5 and longer scales across diverse international student samples.

Main Results:

• XS5 domain scales showed strong correlations (0.74-0.84) with longer established scales.
• No significant differences in predicting external criteria (emotional experience, behaviors) between XS5, S5, and longer scales.
• Controlling for acquiescence improved internal reliability and structural comparability but not predictive validity.

Conclusions:

• The XS5 is a recommended, economical measure of the five-factor model at the domain level, possessing reasonable psychometric properties.
• It offers comparable validity to longer scales for assessing personality domains and predicting behaviors.
• For detailed subscale analysis, the full S5 version is still advised.