Construct and criterion validity of the HEXACO Medium School Inventory Extended (MSI-E).

Area of Science:

• Psychology
• Developmental Psychology
• Educational Psychology

Background:

• The HEXACO personality model offers a comprehensive framework for understanding individual differences.
• Validating observer-based measures is crucial for multi-informant personality assessments in school-aged children.
• Existing measures may not fully capture the nuances of adolescent personality from an external perspective.

Purpose of the Study:

• To validate the observer (Obs) version of the HEXACO Medium School Inventory Extended (MSI-E).
• To establish convergent, divergent, and criterion validity of the HEXACO-MSI-E.
• To assess the reliability and factorial structure of the observer-reported HEXACO-MSI-E.

Main Methods:

• Cross-sectional study involving 1175 adolescents and 854 parent/guardian observers.
• Administration of the HEXACO-MSI-E (self-report and observer versions), Big Five Questionnaire-Children (BFQ-C), Youth Self Report (YSR), and risk behavior/values surveys.
• Statistical analyses including factorial structure confirmation, reliability testing, and validity assessments (convergent, divergent, criterion).

Main Results:

• The factorial structure and reliability of the observer-reported HEXACO-MSI-E were confirmed.
• Convergent and divergent validity were successfully established using parent reports and the BFQ-C.
• Criterion validity was demonstrated, with HEXACO-MSI-E traits showing stronger prediction for self-report criteria.

Conclusions:

• The observer version of the HEXACO-MSI-E is a reliable and valid measure for assessing adolescent personality traits.
• Findings support the use of the HEXACO-MSI-E in multi-informant research and clinical settings.
• The study provides a foundation for future research on adolescent personality development and its correlates.