Eysenck Personality Questionnaire-Revised (Epq-R): A Systematic Review

Eysenck Personality Questionnaire-Revised (EPQ-R): A Systematic Review

Aniedi P. Etuk, James R. Sunday, Dorothy J. Okoro, Gboyega E. Abikoye

Department of Psychology, University of Uyo, Uyo, Akwa Ibom State

DOI: https://dx.doi.org/10.47772/IJRISS.2025.917PSY0005

Received: 27 January 2025; Accepted: 05 February 2025; Published: 05 March 2025

ABSTRACT

The Eysenck Personality Questionnaire has been translated into multiple languages for cross-cultural research and application. Specifically, the questionnaire has been translated into Turkish, Hindi, Nepali, Portuguese and Spanish languages. These translations have been utilized in various studies to assess personality traits such as neuroticism, extraversion, psychoticism, and lying across different cultural and linguistic backgrounds. Psychometric properties of the EPQ translated into various other languages have been examined through reliability and validity analyses, including factor analysis, internal consistency, and construct validity assessments. Despite its widespread use, there is no documented evidence, to our knowledge, of any translations of the EPQ into Nigerian languages (except the Yoruba language). With the huge population of Ibibio-speaking people of Nigeria, translation of the EPQ into Ibibio language and other Nigerian languages will facilitate the study of personality traits in diverse populations, especially in clinical settings where the EPQ is widely used, contributing to a broader understanding of human personality. There is need to undertake a comprehensive review of previous studies that utilized the EPQ with a view to guiding efforts aimed at re-validating and translating the instruments into Nigerian languages.

INTRODUCTION

Eysenck has contributed immensely in the study of personality is one of the most influential of the last 50 years (Boyle et al., 2008). Based on his extensive research, Eysenck came to devise a model of personality which includes three basic traits, Psychoticism (P), Extraversion (E), and Neuroticism (N), which is often referred to as the “Giant Three” or PEN model.

According to Eysenck (1970), personality can be defined as the more or less stable organization of human emotional and behavioral characteristics that reflect an individual’s adaptation to the environment. The structure of personality is composed of three basic nonpathological dimensions, neuroticism, extraversion and psychoticism, which, to a greater or lesser extent, characterize all people and can explain their emotional and behavioral differences (Almiro et al., 2016; Colledani et al., 2018; Eysenck & Eysenck, 1991). These dimensions can be divided as a continuum with two extreme poles (Almiro et al., 2016; 1998; Eysenck & Eysenck, 1975). At first, Eysenck (1959) proposed assessing personality through two dimensions, neuroticism and extraversion. Later, psychoticism was introduced as a third dimensions in the Eysenck Personality Questionnaire (EPQ, Eysenck & Eysenck, 1975). The EPQ represents significant refinement in the description of personality, using only three dimensions, to which the lie scale/social desirability scale was added as a validity scale (Eysenck, 1998; Eysenck & Eysenck, 2008; Furnham et al., 2008).

For nearly 40 years, Hans and Sybil Eysenck developed, updated, validated, and refined their personality measures (Boyle et al., 2008). The last revision of their instruments consists of 100 items and includes four scales, three for the assessment of PEN traits and a Lie (L) scale that detects social desirability bias (Eysenck et al., 1985). Short and abbreviated versions of the instrument, that assess the four dimensions through 48 and 24 items respectively (12 or 6 items for each scale), were also developed. These brief versions demonstrated acceptable psychometric properties and obtained great approval in the cross-cultural, scientific, and professional fields (Eysenck & Barrett, 2013; McLarnon & Romero, 2020), due to their usefulness in the assessment of personality when time is limited. However, some criticisms have been raised, mainly concerning the P scale (low range of scoring, skewed positive distribution, and low internal consistency maybe due to a multifaceted structure). Moreover, several studies indicated that some items of P, N, and L scales exhibit differential item functioning (DIF) across gender (e.g., Colledani et al., 2018; Escorial & Navas, 2007; Karanci et al., 2007).

Recently, a new abbreviated version of the Eysenck Personality Questionnaire-Revised (EPQ-R) has been developed in the Italian context, that aimed to reduce these shortcomings (Colledani et al., 2019a). The authors used item-level statistics and procedures introduced within the framework of multidimensional item response theory (MIRT), that have been proved to be useful for the development of abbreviated instruments (Anselmi et al., 2015; Bock, 1997; Colledani, 2018; Colledani et al., 2018; Colledani et al., 2019b; Haberman et al., 2008; Reckase, 2009; Thissen & Steinberg, 2009). These methods allowed for selecting, from the full-length version of the instrument, 24 items with simple structure, good discrimination, and coverage of the latent trait continua, and without gender DIF and misfit. The scales developed with this procedure were found to outperform the previous ones in reliability (even if the P scale remained the most problematic) and approximation of the measures obtained with the full-length test.

Furthermore, research on personality with Eysenck Personality Questionnaire Revised has also focused on the assessment and measurement of personality traits. These measures can provide valuable insights into an individual’s personality characteristics and can be used to predict behavior, assess mental health, and inform psychological interventions which has been effective over the years with language barrier being one of its limitations. The purpose of the current review was to collate, synthesize, and evaluate the available research on the translation of Eysenck Personality Questionnaire into various languages.

METHOD

This systematic review used the abridged guidelines for preferred reporting items for systematic reviews and meta-analyses (Moher et al., 2015).

Search Strategy

A systematic search of the literature was conducted using the PRISMA strategy (Moher et al., 2015). The databases reviewed for this literature review included PubMed, and Google Scholar. The literature searches took place between September 2023 and January 2024. The search terms and Boolean operators were use with the following keywords: Eysenck personality questionnaire, translation and cross-validation, psychometric properties, factor analysis, personality. This systematic literature search was applied to abstracts, keywords, and titles of the articles. Furthermore, hand searches were conducted on the reference sections of the full text review articles and any meta-analyses/systematic reviews found in the search. In order to improve quality, grey literature was excluded as these have not undergone peer review and are therefore not bound by high standards of quality, which could limit the ability to draw firm conclusions (Adams et al., 2017).

Selection/Eligibility Criteria

Studies were included in this study if they met the following criteria:

1.Published within a peer-reviewed journal between 2000 to date.

2.Not a systematic review or meta-analysis.

3.Available in English.

Studies were excluded if they: (1) if they were conference papers and other none peer review publications, (2) if they were published before 2000. No restrictions were placed on the age of participants.

RESULTS

Dazzi (2011) examined the factorial structure of the Revised Eysenck personality questionnaire (Eysenck & Eysenck, 1991) in the Italian context and present its psychometric properties. Data from a sample of volunteers belonging to different professional categories and Italian regions were used. The factorial structure of EPQ-R was examined using confirmatory factor analysis. Also, invariance across gender was tested by means of a multi-group analysis. Findings confirm the dimensions of the Eysenck personality model for males and females in the Italian context. The invariance across gender was supported. Reliabilities of the subscales were satisfactory. The revised form of the questionnaire can be confidently used also in the Italian context.

Karanci et al. (2007) examined the reliability and the validity of the Turkish translation of the Eysneck Personality Questionnaire Revised-abbreviated Form (EPQR-A) (Francis et al., 1992), which consists of 24 items that assess neuroticism, extraversion, psychoticism, and lying. The questionnaire was first translated into Turkish and then back translated. Subsequently, it was administered to 756 students from 4 different universities. The Fear Survey Inventory-III (FSI-III), Rosenberg Self-Esteem Scales (RSES), and Egna Minnen Betraffande Uppfostran (EMBU-C) were also administered in order to assess the questionnaire’s validity. The internal consistency, test-retest reliability, and validity were subsequently evaluated. Factor analysis, similar to the original scale, yielded 4 factors; the neuroticism, extraversion, psychoticism, and lie scales. Kuder-Richardson alpha coefficients for the extraversion, neuroticism, psychoticism, and lie scales were 0.78, 0.65, 0.42, and 0.64, respectively, and the test-retest reliability of the scales was 0.84, 0.82, 0.69, and 0.69, respectively. The relationships between EPQR-A-48, FSI-III, EMBU-C, and RSES were examined in order to evaluate the construct validity of the scale. Our findings support the construct validity of the questionnaire. To investigate gender differences in scores on the subscales, MANOVA was conducted. The results indicated that there was a gender difference only in the lie scale scores. Their findings largely supported the reliability and validity of the questionnaire in a Turkish student sample. The psychometric characteristics of the Turkish version of the EPQR-A were discussed in light of the relevant literature.

Alexopoulos & Kalaitzidis (2004) evaluated the reliability, internal and test–retest, concurrent and construct validity of the Eysenck Personality Questionnaire-Revised Short Scale (EPQ-R S) in a Greek sample. The EPQ-R S is a 48-self-report questionnaire to assess the dimensions of personality, neuroticism, extraversion, psychoticism. It also includes a Lie scale. The test was translated/adapted by the authors and back-translated by a person whose native language was English. The sample consisted of 946 individuals (422 males, 524 females) aged 16–73-years-old. The EPQ-R S and the Eysenck Personality Questionnaire-Adult (EPQ-A) as the latter was adapted for the Greek population by Demetriou were used to find the concurrent validity of the scale. Reliability coefficients both internal and test–retest, as well as mean inter-item correlations were found to be satisfactory for E, N, L, and low for P. The E, N, L dimensions of EPQ-R S had high correlations with the corresponding dimensions of EPQ-A, but not the P. Finally, a factor analysis of the test indicated the existence of four factors, E, N, P, L which was not confirmed by CFA.

Wilson & Doolabh (1992) evaluated the internal consistency, factorial validity and equivalence of the several forms of Eysenck’s personality inventories currently used in Zimbabwe. 670 (416 male, 254 female) Zimbabwean secondary and tertiary students completed each of the following Eysenck questionnaires: the Eysenck Personality Inventory (EPI), the Eysenck Personality Questionnaire (EPQ), the Eysenck Personality Questionnaire-Revised (EPQ-R), the short-version Eysenck Personality Questionnaire-Revised (EPQ-RS) and the African version of the Eysenck Personality Questionnaire (EPQ-A). Results provided further cross-cultural support, using several different instruments, for the transferability of Eysencks’ four personality dimensions: Extraversion (E), Neuroticism (N), Lie (L) and Psychoticism (P). The psychometric performance of the E and L scales of the EPI was moderate. The E, N and L scales of the EPQ, EPQ-R and EPQ-A possessed acceptable reliability and validity. Although a P factor frequently emerged, its reliability and factorial validity were modest. Correlations between the E, N and L scales of the different EPQ versions were high. The existing E, N and L scales of the EPQ, EPQ-R and EPQ-A could be used in Zimbabwe, but would probably benefit from minor revision. However, careful refinement of the measurement of P is desirable.

Caruso et al. (2001) conducted a reliability generalization study on data from 69 samples found in 44 studies that employed the Psychoticism (P), Extraversion (E), Neuroticism (N), and Lie (L) scales of the Eysenck Personality Questionnaire (EPQ) or EPQ-Revised. The reliability of the scores varied considerably between scales, with P scores tending to have the lowest reliability. Hierarchical regression analyses revealed that a larger standard deviation of scores was associated with higher score reliability for all four EPQ scales. More variability in age was associated with higher score reliability for the P scale and the L scale. Samples composed of students provided scores with higher reliability than those composed of other types of individuals for the P scale. Several other potential predictors (form, language of administration, average score, average age, gender composition, and number of items per scale) were not significantly related to score reliability.

Morfaki (2021) conducted a study on Personality and Leadership, the Short-Form Revised Eysenck Personality Questionnaire: A Greek edition (EPQ-RS-GR). The study aimed at evaluating the reliability of the Eysenck Personality Questionnaire-Revised Short Scale (EPQ-RS) in a Greek sample. The study sampled 332 individuals, (166 males and 166 females), undergraduate students, attending the University of Piraeus in Business Administration Department, who completed the Greek translation of the EPQ-RS. They were randomly recruited among first year students. 48-item Eysenck Personality Questionnaire-Revised Short Scale (EPQ-R Short Scale), a self-report questionnaire, developed to assess three dimensions of personality, neuroticism (stability/emotionality), extraversion (extraversion/introversion) and psychoticism, for adults, which also includes a lie scale for the revelation of falsehoods was used for data gathering. The questionnaire was translated into Greek by a bilingual Greek national and then back-translated into English by a second bilingual Greek national in order to test for inaccuracies and ambiguities. Where the retranslated English version contained inconsistencies, both translators were consulted to determine the appropriate solution. This content-based verification provided clear support for scoring the neuroticism, extraversion and lie scale items as suggested by Eysenck, Eysenck & Barrett (1985). After the content-based analysis the Greek version of EPQ-RS (here after referred as EPQ-RS-GR) was administered on the participants in order to examine its psychometric properties. The results of Cronbach’s alpha method indicated the following alpha coefficients for the four scales: extraversion, 0.7153; neuroticism, 0.8129; psychoticism, 0.5114; lie scale, 0.6611. The results of item rest of test correlations ranged from 0.336 to 0.615 for extraversion, from 0.429 to 0.617 for neuroticism, from 0.248 to 0.616 for lie scale and from 0.298 to 0.519 for psychoticism subscale of EPQ –RS-GR. The findings revealed that both the extraversion and the neuroticism scales of the EPQ-RS-GR achieved satisfactory alpha coefficients well in excess of 0.7, the level recommended by Kline (1993). The lie scale with an alpha coefficient of 0.6611 is considered close in regard to Kline’s criterion of 0.7. The psychoticism scale, however, performed moderately with an alpha coefficient of 0.5114. This proposes that due to satisfactory internal consistency scores, the EPQ-RS-GR is a reliable scale for the measurement of various personality traits. Therefore, it is not likely to be attributable to the translation.

Karanci et al. (2007) aimed at examining the reliability and the validity of the Turkish translation of the Eysenck Personality Questionnaire Revised-Abbreviated Form (EPQR-A). A total of 756 students aged between 17 and 32 years (mean: 21.26; SD: 2.33) (374 men and 382 women) from the Departments of Science and Literature, Economic and Administrative Sciences, and Medical and Social Sciences of Ege, Hacettepe, Istanbul, and Samsun 19 Mayıs Universities were included. Eysenck Personality Questionnaire (Eysenck & Eysenck, 1975) and the abbreviated form of the same questionnaire (48-items) (Eysenck, Eysenck & Barrett 1985). EPQR-A consists of 3 sub-scales: extraversion, neuroticism, and psychoticism, each containing 6 items were used for this study. The translation-back translation method was used (Brislin et al., 1973). The study examined the questionnaire that was translated into Turkish by 3 researchers and following the required revisions the Turkish version was back translated by a bilingual individual into English. The back translation was compared with the original form in terms of content and style. The findings revealed: Internal Consistency- EPQR-A items were evaluated with a binary answering system and were not continuous variables, the Kuder-Richardson 20 method was used to determine the internal consistency. Kuder-Richardson alpha coefficients of the scales for extraversion, neuroticism, psychoticism, and lie were 0.78, 0.65, 0.42, and 0.64, respectively. Test-retest reliability- To determine the test-retest reliability of EPQR-A, the scale was re-administered to 21 university students 2.5 weeks after the first administration. Pearson’s correlation coefficient was calculated and found to be significant. The test-retest reliability of the extraversion, neuroticism, psychoticism and lie scales was 0.84, 0.82, 0.69, and 0.69, respectively. Validity- The relationship between the subscales of EPQRA, and FSI-III, SPPRS-C subscales (mother overprotection, mother rejection, mother emotional warmth, father over protection, father rejection, and father emotional warmth), and RSES were examined in order to evaluate the construct validity of the scale, and the esults are provided in Table II, including correlations between the sub-dimensions. The correlations between the 3 subscales of EPQR-A, and SPPRS-C, FSI-III, and RSES were found to be in the expected direction. The factor structure of the Turkish form was found to be similar to the factor structures found in other cultures. Similar to other studies in the literature, the subscales of EPQR-A showed high internal consistency, except for the psychoticism subscale. When evaluated in general, it can be proposed that due to high internal consistency scores and acceptable test-retest reliability, the Turkish version of the questionnaire is reliable.

García-González et al. (2021) conducted a study on Eysenck Personality Questionnaire Revised-Abbreviated: invariance gender in Spanish university students. The study has two objectives: a) to examine the factorial structure of the Spanish version of the EPQR-A through an exploratory factor analysis and b) to perform a confirmatory factor analysis to determine the psychometric properties of the Spanish version of the EPQR-A in terms of construct validity in an adult academic population. Sample consisted of 826 university undergraduate students: 79.3% were female (655), with a mean age of 18.9 years (SD = 1.56), and 20.7% were male (171), with a mean age of 19.6 years (SD = 1.99). EPQR-A Questionnaire (Eysenck Personality Questionnaire Revised-Abbreviated) (Francis et al., 1992). The Spanish version of the questionnaire of Sandín et al. (2002) was used for the study. To examine differences in mean score of each dimension, t-test was used. To examine the factorial structure of the EPQR-A, exploratory factor analysis (EFA) was applied to the 24 items of the questionnaire based on a four-dimensional theoretical model. The estimation method was generalized least squares. Means and standard deviations for the EPQR-A dimensions for the total and for a random sample of 50% revealed no statistically significant differences (according to t-test) were observed between the scores for both samples in extraversion and psychoticism (p < .05), statistically significant differences were found in neuroticism (t = 1.86, p < .05) and lie scale (t = 1.59, p < .05). In addition, a comparison of the mean scores by gender was also performed. For the psychoticism and lie scales, males had scores that were significantly higher than those of females. In contrast, females had higher mean scores for the neuroticism scale. There were no statistically significant differences in mean scores for the extraversion scale. For reliability, the KR20 was calculated for the four subscales along with the homogeneity index values of the items that formed the subscales. For extraversion, the KR20 was .824, with homogeneity index values between .504 and .661; for neuroticism, the KR20 was .713, homogeneity index values between .321 and .528; for lie, the KR20 was .567, with homogeneity index values between .143 and .357; and finally, for psychoticism, the KR20 was .459, with homogeneity index values between .194 and .392. To test the criterion validity, the subscales of the EPQR-A were gathered through correlations analysis with the subscales of DEX. According to the results there were significant correlation between neuroticism and the following variables: inhibition (ρ = .167, p < .001, small effect size), in-tentionality (ρ = .366, p < .001, large), executive memory (ρ = .312, p < .001, large), positive affect (ρ = .405, p < .001, large), and negative affect (ρ = .348, p < .001, large). Regarding to extraversion, there were significant and positive correlation with Inhibition (ρ = .128, p < .001, small) and negative correlation with intentionality (ρ = -.200, p < .001, medium) and negative affect (ρ = -.340, p < .001, large). For psychoticism and lie scale, the correlation was positive, significant, and with a generally small effect size with all dimension of the criteria (p < .001). For the purpose of adding information to the validity analysis of the EPQR-A, a correlation analysis was performed between the EPQR-A factors and DEX factors corresponding to dysexecutive syndrome. First, the neuroticism, psychoticism and lie scales were directly and significantly related to all the DEX factors: inhibition, intentionality, executive memory, positive affect and negative affect, presenting relatively high values in the case of neuroticism and positive and negative affect. In contrast, extraversion presented only three significant correlations: direct correlations with inhibition and inverse correlations with intentionality and negative affect. All these data showed that there were generally weak correlations coefficients between subscales of EPQR-A and subscales of DEX.

CONCLUSION

The Eysenck Personality Questionnaire has been translated into multiple languages for cross-cultural research and application. Specifically, the questionnaire has been translated into Turkish Hindi, Spanish and several other languages. These translations have been utilized in various studies to assess personality traits such as neuroticism, extraversion, psychoticism, and lying across different cultural and linguistic backgrounds. The validation and psychometric properties of these translated versions have been examined through reliability and validity analyses, including factor analysis, internal consistency, and construct validity assessments. The successful translations of the Eysenck Personality Questionnaire into different languages have facilitated the study of personality traits in diverse populations, contributing to a broader understanding of human personality across cultures.

REFERENCES

1. Adams, R. J., Smart, P., & Huff, A. S. (2017). Shades of grey: Guidelines for working with the grey literature in systematic reviews for management and organizational studies. International Journal of Management Reviews, 19(4), 432–454.
2. Alexopoulos, D., & Kalaitzidis, I. (2004). Psychometric properties of Eysenck Personality Question-naire-Revised (EPQ-R) Short Scale in Greece. Personality and Individual Differences, 37, 1205-1220. https://dx.doi.org/10.1016/j.paid.2003.12.005
3. Almiro, P.A., Moura, O. & Simoes, M.R. (2016). Psychometric properties of the European Portuguese version of the Eysenck Personality Questionnarie- Revised (EPQ-R). Personality and Individual Differences, 88, 93. https://dx.doi.org/10.1016/j.paid.2015.08.050
4. Anselmi, P., Vidotto, G., Bettinardi, O., & Bertolotti, G. (2015). Measurement of change in health status with Rasch models. Health and Quality of Life Outcomes, 13, Article 16.
   10. https://doi.org/10.1186/s12955-014-0197-x
5. Bock, D. (1997). A brief history of item theory. Educational Measurement: Issues and Practice, 16, 21-33. https://doi.org/10.1111/j.1745-3992.1997.tb00605.x
6. Boyle, G. J., Matthews, G., & Saklofske, D. H. (Eds.). (2008). The SAGE handbook of personality theory and assessment, Vol. 2. Personality measurement and testing. Sage Publications, Inc.
7. Brislin, R., Lonner, W. & Thorndike, R. (1973). Cross-cultural research methods. New York: Wiley.
8. Dazzi, C. (2011). The Eysenck personality questionnaire–Revised (EPQ-R): A confirmation of the factorial structure in the Italian context. Personality and Individual Differences, 50(6), 790-794. https://dx.doi.org/10.1016/j.paid.2010.12.032
9. Caruso, J. C., Witkiewitz, K., Belcourt-Dittloff, A., & Gottlieb, J. D. (2001). Reliability of Scores from the Eysenck Personality Questionnaire: A Reliability Generalization Study. Educational and Psychological Measurement, 61(4), 675-689. https://doi.org/10.1177/00131640121971437
10. Colledani, D. (2018). Psychometric properties and gender invariance for the Dickman Impulsivity Inventory. TPM – Testing, Psychometrics, Methodology in Applied Psychology, 25, 49-61. https://doi.org/10.4473/TPM25.1.3
11. Colledani, D., Anselmi, P., & Robusto, E. (2018). Using Item Response Theory for the development of a new short form of the Eysenck Personality Questionnaire-Revised. Frontiers in Psychology, 9, Article 1834. https://doi.org/10.3389/fpsyg.2018.01834
12. Colledani, D., Anselmi, P., & Robusto, E. (2019a). Development of a new abbreviated form of the Eysenck Personality Questionnaire-Revised with multidimensional item response theory. Personality and Individual Differences, 149, 108-117. https://doi.org/10.1016/j.paid.2019.05.044
13. Colledani, D., Anselmi, P., & Robusto, E. (2019b). Using multidimensional item response theory to develop an abbreviated form of the Italian version of Eysenck’s IVE questionnaire. Personality and Individual Differences, 142, 45-52. https://doi.org/10.1016/j.paid.2019.01.032
14. Escorial, S., & Navas, M. J. (2007). Analysis of the gender variable in the Eysenck Personality Questionnaire –Revised scales using differential item functioning techniques. Educational and Psychological Measurement, 67, 990-1001. https://doi.org/10.1177/0013164406299108
15. Eysenck, H.J. (1959). Manual of the Maudsley personality inventory. London: University of London Press.
16. Eysenck, H. J. (1970). The structure of human personality. 3rd ed. North Yorkshire: Methuen Publishing.
17. Eysenck, H.J., & Eysenck, S.B.G. (1975). Manual of the Eysenck personality questionnaire. London: Hodder & Stoughton.
18. Eysenck, S. B. G., Eysenck, H. J., & Barrett, P. (1985). A revised version of the psychoticism scale, Personality and Individual Differences, 6, 21-29.
19. Eysenck, H.J., & Eysenck, S.B.G. (1991). Manual of the Eysenck personality scale (adults). London: Hodder and Stoughton.
20. Eysenck, H.J. (1998). Dimensions of personality. New Brunswick: Transaction Publishers.
21. Eysenck, H.J., & Eysenck, S.B. (2008). EPQ-R: Cuestionario Revisado de Personalidad de Eysenck: Versiones completa (EPQ-R) y abreviada (EPQ-RS) [Revised Eysenck Personality Questionnaire: Complete (EPQ-R) and abbreviated (EPQ-RS) versions] (3ª ed.). Madrid: TEA Ediciones.
22. Eysenck, S., & Barrett, P. (2013). Re-introduction to cross-cultural studies of the EPQ. Personality and Individual Differences, 54, 485-489. https://doi.org/10.1016/j.paid.2012.09.022
23. Francis, L.J., Brown, L.B., & Philipchalk, R. (1992). The development of an abbreviated form of the Revised Eysenck Personality Questionnaire (EPQR-A): Its use among students in England, Canada, the USA and Australia. Personality and Individual Differences, 13(4), 443-449. https://dx.doi.org/10.1016/0191-8869(92)90073-X.
24. Furnham, A., Eysenck, S.B., & Saklofske, D.H. (2008). The Eysenck personality measures: Fifty years of scale development. In G.J. Boyle, G. Matthews, & D.H. Saklofske (Eds.), The SAGE handbook of personality theory and assessment-Vol. 2: Personality measurement and testing (pp. 199–218). London: SAGE.
25. García-González, J. M., Vergara-Moragues, E., Muñoz, J. J. F. & García-Moreno, L. M. (2021). Eysenck Personality Questionnaire Revised-Abbreviated: invariance gender in Spanish university students. Electronic Journal of Research in Educational Psychology, 19(1), 205-222.
26. Haberman, S. J., von Davier, M., & Lee, Y.-H. (2008). Comparison of multidimensional item response models: Multivariate normal ability distributions versus multivariate polytomous ability distributions (RR-08-45). Educational Testing Service.
27. Karanci, A. N., Dirik, G. & Yorulmaz, O. (2007). Reliability and Validity Studies of Turkish Translation of Eysenck Personality Questionnaire Revised-Abbreviated. Türk Psikiyatri Dergisi, Turkish Journal of Psychiatry; 18(3)
28. Kline P. (1993). The handbook of psychological testing. Routledge, editor. London.
29. McLarnon, M. J. W., & Romero, E. F. (2020). Cross-cultural equivalence of shortened versions of the Eysenck Personality Questionnaire: An application of the alignment method. Personality and Individual Differences, 163, Article 110074. https://doi.org/10.1016/j.paid.2020.110074
30. Moher, D., Shamseer, L., Clarke, M., Ghersi, D., Liberati, A., Petticrew, M., Shekelle, P., & Stewart, L. A. (2015). Preferred reporting items for systematic review and meta-analysis protocols (PRISMA-P) 2015 statement. Systematic Reviews, 4(1),1. doi: 10.1186/2046-4053-4-1.
31. Morfaki, C. (2021): Personality and Leadership the Short-Form Revised Eysenck Personality Questionnaire: A Greek edition (EPQ-RS-GR), SPOUDAI – Journal of Economics and Business, 71(3/4), 13-22.
32. Reckase, M. D. (2009). Multidimensional item response theory: Statistics for social and behavioral sciences. Springer.
33. Sandín, B., Valiente, R.M., Chorot, P., Montes, M.O., & Germán, M.A.S. (2002). Versión española del cuestionario EPQR-Abreviado (EPQR-A)(I): Análisis exploratorio de la estructura factorial. Revista de Psicopatologíay Psicología clínica, 7(3), 195-205.
34. Thissen, D., & Steinberg, L. (2009). Item response theory. In R. Millsap & A. Maydeu- Olivares (Eds.), The SAGE handbook of quantitative methods in psychology (pp. 148-177). Sage.
35. Wilson, D.J., & Doolabh, A. (1992). Reliability, factorial validity and equivalence of several forms of the Eysenck Personality Inventory/Questionnaire in Zimbabwe. Personality and Individual Differences, 13(6), 637–643. https://dx.doi.org/10.1016/0191-8869(92)90234-G.