The Eysenck Personality Questionnaire Revised – Abbreviated (EPQR-A): psychometric properties of the Brazilian Portuguese version

Abstract Introduction The Eysenck Personality Questionnaire Revised – Abbreviated (EPQR-A) consists of 24 items for assessment of the three fundamental personality traits (psychoticism, extraversion, and neuroticism) and a validity scale (lie scale). Our objectives were to assess the psychometric properties of a version of this instrument culturally adapted for Brazil. Method 321 participants were recruited using a non-probabilistic method. Results Internal consistencies ranged from minimally acceptable to respectable, except for the psychoticism domain. Higher neuroticism scores were associated with higher depression and anxiety scores, higher extraversion scores were associated with lower levels of depression symptoms, and higher psychoticism scores were associated with higher levels of depression symptoms. Conclusion Our findings describe sustainable psychometric properties for the Brazilian Portuguese version of EPQR-A.


Introduction
According to Eysenck, personality can be defined as a more or less stable and enduring organization of a person's character (conative behavior system), temperament (affective behavior system), intellect (cognitive behavior system), and physique (bodily configuration and neuroendocrine endowment), which determines their unique adjustment to the environment. 1 Eysenck's personality model considers the existence of what he called superfactors, dimensions, or traits. According to this model, the three fundamental dimensions of personality are psychoticism (P), extraversion (E), and neuroticism (N). Each of these dimensions is expressed in terms of a continuum, and people can be classified at any point of the scales, from extremes to median points. 2 In the E dimension, people are shy and retracted on one side (introversion) and sociable and uninhibited on the other (extraversion). The same happens with the N dimension: the neurotic or emotionally unstable personality is located at one extreme and the emotionally stable personality lies at the other.
Individuals with high N scores are overly emotional, anxious, and depressed, frequently experience feelings of guilt, have low self-esteem, and tend to suffer from psychosomatic disorders. The opposite happens with stable individuals, who are typically calm, steadfast, easygoing, and able to control their emotions. The P dimension is characterized by impulsivity on one side and impulse control on the other. The main characteristics of high P scores are hostility, cruelty, lack of empathy, and nonconformism. Eysenck believed that high levels of P are linked to increased vulnerability to psychosis and considered that the biological bases of personality could provide an explanation for certain behaviors through the physiological functioning of the central nervous system. 2,3 The Eysenck Personality Questionnaire (EPQ) contains 90 items 4

and the Revised Eysenck Personality
Questionnaire (EPQ-R) contains 100 items. 3 The EPQ has the same factorial structure as the EPQ-R, but the original version had some psychometric limitations related to the P domain and the revised version of the questionnaire was the result of efforts to fix this problem. Reliability indices for the new P domain were improved and achieved acceptability, but were nevertheless not as high as those for the other domains. It should however be remembered that the P scale explores characteristics such as hostility, cruelty, little evidence of socialization, and lack of empathy, which may cause the lower reliability levels. 3 One of the consequences of the continuous development and improvement of these scales was a progressive increase in questionnaire size. Although some of these instruments, such as the

Measures
Depression symptoms were assessed with the PHQ-9 and anxiety symptoms were assessed using the GAD-2 questionnaire. Personality dimensions were assessed using the EPQR-A.

PHQ-9
The PHQ-9 is a nine-item scale that assesses the intensity and degree of incapacitation of nine depression symptoms according to the depression criteria described in the DSM-V. 18,19 Each item has four possible answers (not at all, several days, more than half the days, and nearly every day), scored from 0 to 3 points. A depression episode was defined as presence of five or more items of the PHQ-9, at least one of which was the first or second item. The Cronbach's alpha coefficient for the PHQ-9 was 0.88 in our sample.

GAD-2
The GAD-2 is a two-item questionnaire on the anxiety symptoms "feeling nervous, anxious, or on edge" and "not being able to stop or control worrying." 20 Each item has four possible answers (not at all, several days, more than half the days, and nearly every day), scored from 0 to 3 points. Generalized anxiety was defined as when the participant's GAD-2 score (sum of the scores for both items) was greater than or equal to 3. The Cronbach's alpha coefficient for the GAD-2 was 0.86 in our sample.

EPQR-A
The EPQR-A consists of 24 items divided into four scales: N, E, P, and L. Each scale has six items, each of them with a dichotomous response format (yes or no); each answer is scored specifically, according to the scale, as 0 or 1. Scoring for each question is predetermined because some questions have reverse coding. 7

Procedures
Participants were recruited by sharing the research protocol via social media in a non-probabilistic method.
We conducted an online self-report survey in order to avoid spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Data on age, gender, education, marital status, ethnicity, occupation, depression and anxiety symptoms, and personality were collected from July to August of 2020.
The online questionnaire was presented in Google

Statistical analyses
Descriptive data were presented using sums,

Factor analysis
The  Figure 1

Convergent validity
The correlations (Pearson's correlation coefficient

Multiple linear regression
The linear relationships between EPQR-A domains and gender (coded 0 for female and 1 for male), age, PHQ-9 score, and GAD-2 scores assessed with multiple linear regression are shown in Table 3. The N domain higher L scores were found in older participants, as demonstrated by previous studies. 30,31 Finally, the L domain showed a negative relationship with PHQ-9 (β = -0.215), indicating that higher L scores were associated with lower levels of depression symptoms.

Discussion
This is the first study to culturally adapt the EPQR-A for Brazil and to assess its psychometric properties in   were observed among patients with major depressive disorder when compared to healthy controls. 35 Another study found neuroticism was a vulnerability factor for depression. 36 Other studies showed extraversion was also significantly lower in depressed individuals. 33,34 Regarding the GAD-2 questionnaire, the N, E, and L domains were found to have significant correlations with anxiety scores. The only domain with a positive correlation was N, meaning that individuals with higher N scores tended to also have higher anxiety scores, while those with higher E and L scores tended to have lower anxiety scores.
In agreement with the literature, higher N scores were associated with female participants. 37,38 Therefore, male gender may be considered a protective factor for N. This information raises a series of questions on the origins of such differences, but a previous study has discussed the possible influence of socially learned gender roles over a biological basis for this distinction, particularly for the neuroticism and psychoticism traits. 37 Moreover, younger age was related to higher N and P scores, while older age was related to higher L scores.
These findings are coherent with those published by Soto et al. 39

Conclusion
The EPQR-A questionnaire could become a reference tool for studies on personality assessment, providing an extensive description of patients' behavioral and emotional characteristics. The EPQR-A questionnaire adapted for Brazilian culture has produced results that reveal satisfactory equivalence to the original version and suggest that this is a reliable and valid option for evaluating personality dimensions in the Brazilian population, although it is important to emphasize the low reliability of the P domain.