Description

The Junior Eysenck Personality Inventory (JEPI-60) is a standardized psychometric instrument designed to assess the fundamental dimensions of personality in children and adolescents according to Hans J. Eysenck’s biological theory of personality. The questionnaire evaluates stable personality characteristics that influence emotional functioning, social behavior, interpersonal relationships, and psychological adjustment during childhood and adolescence. As one of the most widely recognized personality measures for young populations, the JEPI provides a reliable assessment of core personality traits while maintaining a simple administration format suitable for school-aged children.

The instrument consists of 60 self-report items and evaluates two principal personality dimensions: Extraversion, which reflects sociability, activity, enthusiasm, and outgoing behavior, and Neuroticism, which measures emotional instability, anxiety, and vulnerability to psychological distress. In addition, the questionnaire includes a Lie Scale, designed to assess the tendency of respondents to provide socially desirable answers rather than fully accurate self-descriptions. The inclusion of this scale improves the interpretability of the results by identifying possible response bias during questionnaire administration.

The Greek version of the questionnaire was translated, culturally adapted, and psychometrically evaluated by D. S. Alexopoulos, following standardized translation procedures, including independent back-translation by a native English speaker to ensure conceptual equivalence with the original instrument. Owing to its strong theoretical foundation and extensive validation, the JEPI is widely used in developmental psychology, educational psychology, school counseling, child and adolescent psychiatry, behavioral sciences, personality research, and psychological assessment.

Data Analysis and Use

Data obtained from the Junior Eysenck Personality Inventory (JEPI-60) are analyzed using comprehensive psychometric and statistical procedures designed to evaluate children’s and adolescents’ personality characteristics across the three questionnaire scales. Individual responses are scored dichotomously and aggregated to calculate separate scores for Extraversion, Neuroticism, and the Lie Scale, allowing the construction of standardized personality profiles.

Psychometric evaluation typically includes analyses of internal consistency using Cronbach’s alpha coefficient, together with assessments of test–retest reliability, construct validity, content validity, criterion validity, convergent validity, discriminant validity, and exploratory and confirmatory factor analyses (EFA/CFA). Additional analyses frequently include composite reliability, measurement invariance across age and sex, and item-response analyses to ensure stable psychometric performance across diverse child and adolescent populations.

The Greek standardization study included a large sample of 2,159 students, comprising 1,059 girls and 1,086 boys, attending the final three grades of primary school and all three grades of junior high school, aged 9 to 16 years. Validation analyses demonstrated statistically significant correlations between the JEPI dimensions and the corresponding scales of the Junior Eysenck Personality Questionnaire (JEPQ), supporting satisfactory convergent validity, while correlations with unrelated personality measures were substantially lower, supporting discriminant validity. Reliability analyses indicated satisfactory psychometric performance for most dimensions, although some coefficients varied across individual scales.

Statistical analyses commonly include descriptive statistics, Pearson or Spearman correlation analyses, multiple regression models, structural equation modeling (SEM), cluster analysis, latent profile analysis, and comparative procedures such as independent-samples t-tests and analysis of variance (ANOVA). These approaches enable researchers to investigate relationships between personality traits and variables including academic achievement, emotional adjustment, behavioral problems, resilience, self-esteem, social functioning, and psychological well-being.

Objective

The primary objective of the Junior Eysenck Personality Inventory (JEPI-60) is to provide a reliable and valid assessment of the major dimensions of personality in children and adolescents, according to Eysenck’s theoretical model. The questionnaire enables psychologists, educators, school counselors, researchers, and child mental health professionals to evaluate stable personality characteristics associated with emotional regulation, behavioral functioning, interpersonal relationships, and developmental adjustment.

The instrument supports both educational practice and scientific research by facilitating the identification of individual personality profiles, investigating developmental differences, and examining the relationship between personality and educational, emotional, social, and behavioral outcomes. Furthermore, it contributes to evidence-based psychological assessment and intervention planning aimed at promoting healthy psychological development and adaptive functioning throughout childhood and adolescence.

Scoring

The Junior Eysenck Personality Inventory (JEPI-60) consists of 60 dichotomous self-report items, with participants responding “Yes” or “No” to each statement. Standard scoring assigns 1 point to responses indicating the presence of the measured personality characteristic and 0 points to the alternative response. For reverse-scored items, the scoring is inverted, with “No” receiving 1 point and “Yes” receiving 0 points.

Separate scores are calculated for the Extraversion, Neuroticism, and Lie scales by summing the corresponding item responses. Higher Extraversion scores indicate greater sociability, activity, and outgoing behavior, whereas higher Neuroticism scores reflect greater emotional instability, anxiety, and vulnerability to stress. Higher scores on the Lie Scale indicate a stronger tendency toward socially desirable responding, suggesting that respondents may have presented themselves in an overly favorable manner.

Interpretation of questionnaire scores should always be supported by comprehensive psychometric evaluation, including analyses of Cronbach’s alpha coefficients, construct validity, criterion validity, exploratory and confirmatory factor analyses, normative comparisons, and cross-cultural validation, ensuring accurate and reliable assessment across diverse child and adolescent populations.

References

Alexopoulos, D. S. (2004). Reliability and Validity of the Junior Eysenck Personality Inventory (JEPI) in Greece. Psychology, 11(3), 402–422.

Eysenck, H. J., & Eysenck, S. B. G. (1963). Junior Eysenck Personality Inventory (JEPI). San Diego, CA: Educational and Industrial Testing Service (EdITS).

Eysenck, H. J., & Eysenck, M. W. (1985). Personality and Individual Differences: A Natural Science Approach. Plenum Press.

Matthews, G., Deary, I. J., & Whiteman, M. C. (2009). Personality Traits (3rd ed.). Cambridge University Press.