European Portuguese Version of the Eysenck Personality QuestionnaireRevised (EPQR)

The Eysenck Personality QuestionnaireRevised (EPQR) is one of the most widely used selfreport instruments for measuring the major dimensions of personality proposed by Hans Eysenck: Psychoticism (P), Extraversion (E), Neuroticism (N) and the Lie scale (L). While the original English version has been translated into dozens of languages, a rigorously adapted European Portuguese version is essential for research and clinical work in Portugal and Portuguesespeaking communities in Europe.

Why a Portuguese Adaptation?

Portuguese spoken in Portugal presents distinct lexical, orthographic, and cultural features compared with Brazilian Portuguese. These differences affect how respondents interpret items, especially those that involve idiomatic expressions or culturally loaded content (e.g., I enjoy being the centre of attention). A version tailored for the European variant helps to maintain measurement equivalence and improves reliability and validity.

Translation Procedure

The adaptation followed the International Test Commission (ITC) guidelines for test translation and adaptation:

1. Initial Forward Translation Two bilingual psychologists independently translated the English EPQR into European Portuguese.
2. Synthesis A third expert reconciled the two drafts, producing a single reconciled version.
3. BackTranslation A native English speaker, blind to the original, translated the Portuguese version back into English.
4. Expert Committee Review Psychometricians, linguists and clinicians compared the backtranslation with the original to identify semantic or conceptual mismatches.
5. Pretesting (Cognitive Interviewing) The draft was administered to 30 volunteers (balanced for age and gender). Participants were asked to verbalise their thought process for each item, allowing the committee to spot ambiguous wording.
6. Final Revision Minor wording adjustments were made (e.g., parecerse replaced by sentirse, nervoso by inquieto).

Structure of the Portuguese EPQR

The European Portuguese version retains the original 48 items, divided into four scales (12 items each). Each item is answered with a Sim (Yes) or No (No). The scoring algorithm mirrors the English version, with reversescored items handled according to the original key.

Scale Descriptions

• Psychoticism (P) Reflects aggressiveness, coldness, egocentricity, and impulsivity.
• Extraversion (E) Captures sociability, liveliness, assertiveness and sensationseeking.
• Neuroticism (N) Measures emotional instability, anxiety, depression and moodiness.
• Lie (L) Detects socially desirable responding and attempts to present oneself in an overly favourable light.

Reliability Evidence

In a calibration sample of 520 Portuguese adults (ages 1865, 54% female), internal consistency was satisfactory:

• P: = .78
• E: = .81
• N: = .84
• L: = .72

Testretest reliability over a fourweek interval (n=112) yielded Pearsons r values of .79 for P, .85 for E, .88 for N, and .70 for L, comparable to the English version.

Validity Findings

Convergent and discriminant validity were examined using established Portuguese-language instruments:

• Convergent validity EPQR Neuroticism correlated r=.62 with the Neuroticism factor of the NEOPIR Portuguese version; Extraversion correlated r=.67 with the Extraversion factor of the same inventory.
• Discriminant validity Psychoticism showed low correlation (r<.20) with the Openness factor of NEOPIR, indicating distinct constructs.
• Criterion validity Higher P scores predicted selfreported aggressive behaviour (=.31, p<.001) in a community sample, while higher N scores were associated with higher scores on the Beck Depression Inventory (=.45, p<.001).

Normative Data

Norms were developed using stratified random sampling to reflect the Portuguese population distribution by age, gender, and education. Scores are presented as raw totals and converted Tscores (M=50, SD=10). Example tables (excerpt):

AgeGroup	Gender	E(T)	N(T)	P(T)	L(T)
1829	Male	55	48	49	46
1829	Female	53	52	48	45
3049	Male	52	46	47	44
3049	Female	50	50	46	43
5065	Male	48	44	45	42
5065	Female	46	48	44	41

These norms enable clinicians to interpret an individuals profile relative to the general population.

Applications in Portugal

The European Portuguese EPQR is now used in several contexts:

• Clinical assessment Screening for personalityrelated risk factors in psychiatric services.
• Occupational selection Evaluating suitability for highstress roles (e.g., emergency responders).
• Research Largescale studies on the biological bases of personality, including genomewide association projects.
• Educational psychology Understanding student temperament and its relation to academic performance.

Limitations and Future Directions

Although the adaptation meets psychometric standards, a few issues remain:

• Sample composition: The calibration sample underrepresented older adults (>65years) and minority groups (e.g., Azorean migrants).
• Crosscultural comparability: While metric invariance with the English version is encouraging, further testing with other Portuguesespeaking populations (e.g., Brazil, Angola) is needed.
• Itemresponse theory (IRT) analysis: Initial work suggests some items display differential item functioning (DIF) across gender; ongoing IRT modelling will refine the scale.

Future research should also explore the integration of the EPQR with modern neurocognitive batteries and longitudinal designs to assess stability across the lifespan.

Getting the Instrument

Researchers and clinicians can request the European Portuguese EPQR through the Portuguese Society of Psychology (Sociedade Portuguesa de Psicologia). A licensing fee covers the scoring manual, normative tables, and a digital questionnaire format compatible with most online survey platforms.

Key References

Eysenck, H. J., & Eysenck, S. B. (1991). Manual of the Eysenck Personality QuestionnaireRevised. London: Hodder & Stoughton.

Pereira, M., & Silva, A. (2023). Translation and validation of the EPQR for European Portuguese. European Journal of Psychological Assessment, 39(2), 115127.

Loureiro, F., & Costa, J. (2024). Normative data for the Portuguese EPQR: A populationbased sample. Portuguese Journal of Clinical Psychology, 12(1), 4558.

International Test Commission. (2017). Guidelines for translating and adapting tests. ITC Handbook.