General Factor of Personality Questionnaire (GFPQ): only one factor to understand personality?
In the studies of Zuckerman, Khulman & Camac (1988) and Zuckerman, Khulman, Thornquist & Kiers (1991), different factorial solutions were obtained from a large amount of personality scales. The solutions with 5 and 3 personality factors were considered equally satisfactory.
In this sense, it is worth highlighting the combination of Agreeableness and Conscientiousness of the Big Five model (Costa & McCrae, 1992) which contributes to the negative pole of Eysenck's Psychoticism factor (Eysenck, 1991; 1992, a, b; Markon, Krueger & Watson, 2005). Eysenck does not consider O (Openness to experience) in his model.
Therefore, we can consider the Eysencks' model with 3 basic personality factors to be acceptable as a starting point.
Nonetheless, can we consider 3 personality traits to be the minimum number needed to describe the basic personality?
Many theories about personality maintain that the Big Five and the Big Three Models are not comprehensive, and that two higher-order factors exist (the Big Two). Some examples of such are:
1. Two temperaments (Elliot & Thrash, 2002). Approach and avoidance temperaments represent the foundation of several basic dimensions. Through a factor analysis the following finding was obtained: the measures of extraversion, positive emotionality, and behavioral activation system weighted up together on 1 factor (Approach Temperament) and, the measures of neuroticism, negative emotionality, and behavioral inhibition system weighted up on factor 2 (Avoidance Temperament) (Elliot & Thrash, 2002, p. 804). Approach and avoidance temperaments may be seen as extensions of the specific BAS (Behavioral Activation System) and BIS (Behavioral Inhibition System) constructs posited by Gray (Elliot & Thrash, 2002, p. 806).
2. Approach and Avoidance, based on Gray's model (Carver, Sutton & Scheier, 2000). Following these authors, two broad self-regulatory systems underlying both action and affect exist: one system aimed at approach and the other aimed at avoidance or withdrawal.
3. Mental health and behavior control (Becker, 1999). Mental Health is defined as the ability to cope with external and internal demands. It correlates positively and significantly with Extraversion and negatively and significantly with Neuroticism. Behavior Control is characterized by self-control (norm, work and reason orientation and orderliness) vs. spontaneity (hedonism, excitement seeking and feeling orientation and liveliness). It correlates positively and significantly with Conscientiousness and negatively and significantly with Extraversion and Openness to Experience.
4. Alpha and Beta Factors (Digman, 1997). He performed a meta-analysis of the Big Five-factor correlations from 14 studies and found two higher order factors: Alpha (Agreeableness, Conscientiousness, and Emotional Stability) associated with socialisation processes, and Beta (Extraversion and Openness) associated with personal growth.
5. Impulsivity and Withdrawal (Blackburn, Renwick, Donnely & Logan, 2004). These authors found good support for the Big-Two model. A confirmatory factor analysis indicated that the Impulsivity and Withdrawal factor scales of the Antisocial Personality Questionnaire (APQ) provide reasonable markers of the NEO Five Factor Inventory (NEO-FFI) latent factors. The Impulsivity and Withdrawal dimensions reflect basic motivational concerns about power, status, and intimacy. Blackburn, Logan and Renwick (2005) also generated Digman's dimensions, viewing them from their negative poles, and labelling them as "anxious-inhibited" or affiliation, and "acting out" or dominance.
6. Extraversion and Neuroticism as the higher factors of MMPI (Kassebaum, Couch & Slater, 1959). They found two primary factors very similar to Eysenck's N and E. But they also found that P scale loaded.71 on the N factor.
7. Stability and Plasticity (DeYoung, Peterson & Higgins, 2001). These authors replicated Digman's two factor solution of the Big-Five model, and proposed a Big Two model. They obtained two factors: Stability (Agreeableness, Conscientiousness, and Emotional Stability) and Plasticity (Extraversion and Openness). These authors opine, contrary to Digman, that the Big Two represent very basic tendencies, not only socialisation processes and personal growth.
8. Gray (1987) also reformulated his initial theory to indicate that both E and P constitute the BAS (Behavioral Activation System). Torrubia, Avila, Molto & Caseras (2001) obtained a moderate correlation between P and the BAS. Quilty & Oakman (2004) found that global impulsivity measures were related to BAS. P negatively correlated with BIS, but positively with BAS (Jorm, Christensen, Henderson, Jacomb, Korten et al., 1999).
What are the proposed relationships among the Big Two, the Big Three and the Big Five?
Some authors found a positive association between BIS (Behavioral Inhibition System) and N (Neuroticism) and between E (Extraversion) and BAS (Behavioral Activation System) from Eysenck's system (Carver & White, 1994; Heubeck, Wilkinson & Cologon, 1988; Jorm et al., 1999; Zelenski & Larsen, 1999).
Also, Smits & Boeck (2006) found that Extraversion was positively related to BAS and that it was also negatively related to BIS. Similar relationships were obtained by several authors (Heubeck et al., 1998; Jackson & Smillie, 2004; Jorm et al., 1999).
Moreover, Smits & Boeck (2006) found that Neuroticism was positively related to BIS. These authors explained that BIS reflects emotional instability, a reaction towards events that occurred or are expected, and it depends strongly on external and, therefore, varying circumstances.
Smits & Boeck (2006) found that Agreeableness was positively related to BIS and negatively related to BAS. Conscientiousness was negatively related to the BASF subscale (fun seeking scale), and that the BASF is highly related to impulsivity (Zelenski & Larsen (1999).
Is the Big Two model orthogonal?
Agreeableness, Conscientiousness and Emotional Stability can be grouped in Alfa (Digman, 1997), in Stability (DeYoung et al., 2001) or in BIS (Smits and Boeck, 2006) factors. Extraversion and Openness can be grouped in Beta, Plasticity or BAS factors. One is related to Positive Emotionality while the other relates to Negative Emotionality (Carver et al., 2000). These factors can be named as Approach versus Avoidance (Carver et al., 2000). They affirm that: "Two broad self-regulatory systems underlying both action and affect exist: one system aimed at approach and the other aimed at avoidance or withdrawal" (Carver et al., 2000, p.746). It is also possible to name these factors as Extraversion versus Neuroticism (Kassebaum et al., 1959).
It is held that the two factors are orthogonal, although a factorial analysis may lead to a statistical and, therefore, descriptive model as opposed to a possible causal or dynamic model. There is considerable scientific evidence about the non-orthogonality of the referred two big factors, as it is stated in the following.
Furthermore, the correlation studies on these two dimensions are not conclusive. Some examples are:
1. BIS negatively and significantly relates to E (r = -.46, p <.001), but positively relates to N (r =.56, p <.001) (Caseras, Avila & Torrubia, 2003).
2. Withdrawal relates negatively and significantly with E (=.61, p <.001), and positively with N (r =.64, p <.001) (Blackburn, Logan & Renwick, 2005).
3. Moderate but significantly negative correlations were observed between E and N for both females (-.022) and males (-.35), and a small but significant positive correlation was noted between E and P (.16) (Buckingham, Charles & Beh, 2001).
4. DeYoung et al. (2001) obtained a significant positive correlation between the Big Two (ranging from.18 to.28 for the respective samples) in spite of the use of varimax rotation in the statistical analysis.
5. When the oblique rotation method is used, higher correlations are obtained between both big factors, ranging from.20 to.48 for different samples and personality measures (Musek, 2006).
When experimental manipulation is introduced, a dynamic relationship between these two factors is observed. For example, in a rapid visual information processing task, caffeine administration induced arousal, which increases the likelihood of an emission of an impulsive response in vulnerable individuals (Anx-/Imp+). There is an antagonistic effect of BAS on behavioral inhibition (Corr, 2001). This author proposes the joint subsystems hypothesis in contrast to the conventional separable subsystems hypothesis of the independent effects of the BIS and BAS.
Eysenck & Eysenck (1985) suggest that the negative correlation may be due to an underlying relationship between the two super-factors ("partial independence"). For individuals high on N, E and N are related in such a way that there are likely to be more low-E individuals than high-E ones. For individuals low on N, the two dimensions are independent. Autonomic activation (N) can also lead to cortical arousal (E). Only "when strong emotions are involved frequently for long periods do activation and arousal tend to become synonymous" (p. 233).
As Becker (1999) said in relation to the Big Five, a significant intercorrelation between personality variables does not suggest the highest level of description, rather the need for some higher-order constructs.
Three decades ago, Rushton conjectured that "one basic dimension -K- underlies much of the field of personality" (1985, p. 445). But only recently this proposal has been seriously considered. As Musek claimed: "the single factor position is virtually non-existent in hierarchical structural models of personality" (2007, p. 1214). He talks about "the single general factor hypothesis" (p. 1216) and proposes a general factor of personality (The Big One) within the five-factor model which occupies the apex or the hierarchy of personality. Also, Saucier and Goldberg (2003), in the context lexical model, proposed the existence of a single common factor underlying the Big Five. The authors interpreted this factor as the Evaluation factor, expressing socially desirable versus undesirable personality.
Several studies tested the hypothesis of the general factor of personality (GFP) using structural equation model from personality scales battery (Rushton & Irwing, 2008; Musek, 2007; Rushton, Bons & Hur, 2008). Recently, a GFP has been extracted from many personality scales, inventories and questionnaires, such as the Comrey Personality Scales, the Minnesota Multiphasic Personality Inventory-2, the Multicultural Personality Questionnaire (Rushton & Irwing, 2009a), the 16 sets of the Big Five, the Guilford-Zimmerman Temperament Survey, the California Psychological Inventory, the Temperament and Character Inventory (Rushton & Irwing, 2009b), the Multidimensional Personality Questionnaire (Rushton & Irwing, 2009c), the self-, teacher-, and parent ratings on the Big Five Questionnaire and Cloninger's Temperament and Character Inventory from multitrait-multimethod data and cross-national twins (Rushton et al., 2009), the HEXACO model (Veselka et al., 2009a). The GFP is related with trait emotional intelligence (Veselka et al., 2009a; Veselka, Schermer, Petrides, Cherkas & Vernon, 2009b), mental toughness (Veselka et al., 2009b), general intelligence and social desirability (Schermer & Vernon, 2010) and self-esteem (Erdle, Irwing, Rushton & Park, 2010).
Also has been proposed a psychometric approach to assess the general factor of personality from Life History Theory, obtaining the K-Factor (Bogaert and Rusthon, 1989; Figueredo et al., 2006). Twenty scales measuring dimensions related to life history strategy were constructed from MIDUS survey data (Brim et al., 2000). Three factors were constructed: 1) the K-factor, measuring personal, familiar and social functioning; 2) Covitality, measuring physical and mental health, and 3) Personality, constructed from scales for the "Big Five" factors of personality (Figueredo, Vasquez, Brumbach & Schneider, 2007). K-factor, covitality and general personality factor correlated significantly with each other. All of the reliable variance among them was explained by a single higher-order factor called the "Super-K". The genetic covariance between the three factors belongs to the nonadditive variety, which suggests that the three factors coevolved and are mutually coadapted through directional selection (Figueredo & Rushton, 2009). The Mini-K is a 20-item short-form measure of the K-Factor (Figueredo et al., 2006). These measures of GFP are included in a general measure of life history strategies, and they are constructed from the MIDUS'scales. Nevertheless, a questionnaire elaborated and validated to measure specifically the General Factor of Personality has not been created up to day. The main objective of this study is to introduce such a questionnaire.
Moreover, the instrument proposed here is based on a psychobiological theory of personality. Amigo proposed the existence of a single basic trait in the vertex of a hierarchy of personality traits in his Unique Trait Personality Theory (Amigo, 2005; Amigo et al., 2008, Caselles et al. in press). This theory differs from the theories cited up. The explanatory theories about the general factor of personality identify a single common factor, the K-Factor, which underlies a variety of life-history parameters like an assortment of sexual, reproductive, parental, familiar and social behaviors (Rushton, 1990; Figueredo et al., 2006). In a different sense, the principal objective of the Unique Personality Trait Theory is to find the most basic mechanism of organism behavior, the simplest mechanism: the reactivity to external stimuli. In this theory, people are situated around a continuum with respect to the strength and direction of the reactivity to the stimuli, considering the quality of the stimuli. So, people situated in the left extreme pole (extraverted) react rapidly and strongly to the appetitive stimuli, with approximation behavior. People situated in the right extreme pole (introverted) react rapidly and strongly to the aversive stimuli with avoidance behavior. This theory proposes that this basic mechanism of reactivity explains all the behavior complexity, the whole personality and disorders.
Nonetheless, it is necessary to have a specific instrument available to assess the unique personality trait, and the study of its functional relationships with the other traits proposed in the different personality models cited herein. Indeed, this is the essential objective of this study. This super-factor has received different names: single general factor, Big One, general common factor, unique trait, extraversion, or general factor of personality. This last name is the most accepted one at present. So, it is appropriate to name this instrument as General Factor of Personality Questionnaire.
Materials and Methods
A total of 251 participants (90 males and 161 females) were included. These participants were selected from the students and staff at Universities of Valencia (50.6%) and valencian professionals of several types (49.4%). The mean age was 32.13 (SD = 13.98) of ages ranging from 17 to 74 years.
1. EPQ-RS (Eysenck & Eysenck, 1985). The EPQRS is a 48 yes-no response item questionnaire containing four subscales, each one consists of 12 items including: Extraversion, Neuroticism, Psychoticism and Lie.
2. International Personality Disorders Examination (IPDE) (Loranger et al., 1994). It is a 77 yes no response item questionnaire containing 10 subscales, each one consists of 10 items, referred to personality disorders: Paranoid, Schizoid, Schizotypal, Antisocial, Borderline, Histrionic, Narcissistic, Avoidant, Dependent and Obsessive-compulsive.
3. The Sensitivity to Punishment and Sensitivity to Reward Questionnaire (SPSRQ) (Torrubia et al., 2001). The SPSRQ-RS is a 48 yes-no responses item questionnaire containing two subscales: Sensitivity to Punishment (SP, with 24 items) and Sensitivity to Reward (SR, with 24 items).
4. Sensation Seeking V Form Scale (SSS; Zuckerman, Eysenck & Eysenck, 1978). The SSS is a 48 yes-no response item questionnaire containing four subscales, each one consists of 10 items: Thrill and Adventure Seeking (TAS), Experience Seeking (ES), Disinhibition (DIS) and Boredom Susceptibility (BS).
5. The Berkeley Personality Profile (BPP; Harary & Donahue, 1994). The BPP is a 35 Likert response item questionnaire containing five subscales each one consists of 7 items. These scales measure five personality styles: Expressive, Interpersonal, Work, Emotional and Intellectual. These personality styles are related with five dimensions of personality that have come up repeatedly in the Big Five studies.
6. Scales of Anxiety, Depression and Hostility of the SCL-90-R (Derogatis, 1994). The SCL-90-R is a 90 Likert response item (5-points rating scale) containing 9 symptom scales and 3 global indices that evaluate a broad range of psychological problems and symptoms of psychopathology. Three symptom scales are selected: Anxiety, Depression and Hostility.
7. General Factor of Personality Questionnaire (GFPQ). This is the questionnaire presented in this study. The corresponding description is presented in the following.
With questionnaires 1, 2 and 4, versions that had been specially adapted in Spain were used (Ortet, Ibanez, Moro, & Silva, 1997; Lopez-Ibor, Perez, & Rubio, 1996; Perez & Torrubia, 1986, respectively).
Questionnaire 7 initially comprised 40 items, which had been provisionally selected by experts who had attempted to measure the unique personality trait. After calculating the item-scale correlations, 20 items with high correlations were selected. These 20 items make up the GFPQ (General Factor of Personality Questionnaire) which will be analyzed in the sections that follow.
The questionnaire battery was delivered either on hands or sent by e-mail to persons belonging to different cultural and professional fields of the city of Valencia (Spain). The battery was preceded by a set of written instructions about how to fill it out. Participants were not paid for their collaboration but a latter conference about some personal reports was offered to those interested in it. All participants were identified with a pseudonym in order to assure confidentiality.
The tool SPSS 16.0 (SPSS Inc, 2007) was used for the statistical analyses. Bivariate and multivariate analyses were performed with the studied variables. The corresponding results are presented in the following.
The reliability and construct viability of the GFPQ
The GFPQ is a 20 Likert response item questionnaire (the items are described in Table 1), containing two scales with 10 items each: 1) the Extraversion Scale (ES) and the Introversion Scale (IS). This questionnaire attempts to measure the unique personality trait.
The format of a five-level likert item is:
1. Strongly disagree.
3. Neither agree nor disagree.
5. Strongly agree.
In order to compute the total scoring, it is necessary to reverse the scores of the items of the Introversion Scale (items from 11 to 20).
The internal consistency of the GFPQ is acceptable ([alpha] =.74). For the two separate scales, the internal consistency index is higher ([alpha] =.78 for both the ES and the IS).
A factor analysis was proposed. The initial results indicate that the conditions to do the factorial analysis are adequate, with a Kaiser-Meyer-Olkin Measure of Sampling of .801, and a significantly Bartlett's Test of Sphericity (p <.001).
A factor analysis was performed with:
--An extraction method: Principal Component Analysis.
--A rotation method: Oblimin with Kaiser Normalization (5 =.8).
A sub-extraction was performed, looking for two principal factors: Extraversion and Introversion. Both these components explained a similar percentage of variance (18.81% the first and the 17.62% the second). The total variance explained by both components is 36.43%.
The Structure Matrix (with the items from the two scales) is presented in Table 1.
The correlation of the components (-.53) shows an overlap of the items of both scales, and a negative correlation between them is noted.
The criterion to choose a method using oblique rotation was theoretical. After a revision of the literature and given the dimensional proposition of the unique trait, it was considered that the two poles of the continuum would correspond with two factors being non-orthogonal and interrelated. Consequently a high delta (.8) was used. The correlation matrix of the two factors reveals a negative relation (-.53) as indicated upwards.
GFPQ, sex and age
Significant differences are seen in the GFPQ scores according to age and sex. To calculate the statistical differences in the relationship in connection with age, two age groups have been considered with a cut-off point at 30 years of age. The results are shown in Table 2.
GFPQ and basic personality traits
Firstly, we are interested in founding the relationship between the unique trait and the traits of the Big Five model. A regression analysis was performed with GFPQ as a dependent variable and the five factors as independent variables. The principal results are shown in the Table 3.
All the big five factors enter significantly in the regression equation. All these factors predict the unique trait.
It is possible that a second-order factor underlying the big five exists. A factor analysis is performed. The extraction method is Principal Component Analysis and a Varimax rotation.
One single component is extracted, as shown in Table 4. This component explains a percentage of variance of 34.78%. All saturations are the same or up to.50. The saturation of Neuroticism is negative. We elaborate a integrate score of the five factors. This variable correlate positive and significantly with GFPQ (r =.44; p <.001).
Table 5 shows an intercorrelations matrix between the GFPQ and the personality traits of the EPQ, the SPSRQ and the Sensation Seeking Scale. The SPSRQ is composed of two scales: SP (Sensitivity to Punishment) and SR (Sensitivity to Reward).
These results prove interesting. First of all, we observe that the only significant relationship is that between the EPQ traits obtained for E and N (r = -.15;p <.05), and that it presents a low correlation. With regard to the relationships between the EPQ and the SPSRQ factors, we observe that N positively and significantly correlates with SR and SP. For E, the relationship with SR is positive (r =.24; p <.01), but it is negative with SP (r = -.36; p <.01).
The relationships of the SSS with both the EPQ and SPSRQ were as expected. Sensation seeking relates positively and significantly with E and P, while it does not correlate with N. On the other hand, sensation seeking correlates positively and significantly with SR, but does not correlate with SP.
In relation to the UPTQ, the relationships with the rest of the personality dimensions were as expected. So in relation with the EPQ, it positively and significantly correlates with E and P (r =.35 and r =.19, respectively, with p <.01), but correlates negatively with N (= -.42; p <.01). However, the GFPQ correlates positively and significantly with SR (r =.23; <.01), but negatively with SP (r = -.58; p <.01). Finally, the relationship with sensation seeking is positive and significant (r =.58; p <.01).
GFPQ and psychopathology
The relationships between the GFPQ and personality disorders (measured with the IPDE), and with the SCL-90 negative emotion scales (anxiety, depression and hostility), were also in the expected direction.
Therefore regarding the relationship between the unique personality trait and personality disorders, a positive and significant correlation was obtained between the unique trait and the antisocial personality disorder (=.20; p <.01), while a negative and significant correlation was obtained with the anxiety spectrum disorders: obsessive-compulsive (r = -.34; p<.01), dependence (r = -.34; p <.01) and avoidance (r = -.39; p <.01).
On the other hand, a negative and significant correlation was obtained for four serious personality disorders: schizoid (r = -.24; p <.01), schizotypic (r = -.26; p <.01), paranoid (r = -. 14; p <.05) and borderline (r = -. 17; p <.01).
As for the relationship between the unique trait and emotional disorders, Table 6 presents the intercorrelations matrix.
Positive and significant correlation is noted among the three scales of negative emotions. On the other hand, a relationship is also observed between the unique trait and two scales of negative emotions. The two relationships relate negatively and significantly with anxiety (r = -.28; p <.01) and depression (r = -.34; p <.01).
A cluster analysis was done based on the EPQ factors. Two clusters were obtained in order to classify the sample subjects. The results are presented in Tables 7 and 8.
The initial clusters correspond to the combination of extreme scores. We can consider these scores as the extreme poles of the unique personality trait, which fluctuate between neurotic introversion with some aspects of psychoticism and stable extraversion with a high level of psychoticism.
All the subjects have been classified around the final cluster centers. We can see that psychoticism is no longer relevant as a classification criterion, whereas Cluster 1 corresponds to neurotic introversion and Cluster 2 corresponds to stable extraversion.
This classification represents the two poles of the unique personality trait. If we assign each subject a category, we are able to obtain their relationship with the unique personality trait. Therefore, the relationship between the clusters and the unique personality trait is positive and significant (r =.41; p <.01). We also obtain a significant difference of means from the unique personality trait for the two groups of subjects corresponding to each cluster (= -8.47; p <.001).
The results of this study support the existence of a general factor of personality (GFP), and one that is sufficient to describe the complete personality. This trait is represented by a continuum whose poles are introversion and extraversion. The construct Extraversion/Introversion is understood in a wider sense than the commonly accepted one, because it is considered as a bipolar dimension that measures the organism's relationship with its environment. Thus, the left pole corresponds to stimuli-seeking and approach behavior (Extraversion) and the right pole corresponds to stimuli-avoidance and stress behavior (Introversion). Besides, this trait is situated on the top of a hierarchical diagram of the personality structure.
We have constructed the General Factor of Personality Questionnaire (GFPQ) with 20 items composed of two scales with 10 items each. The scales are interrelated, just as the correlation indicates (-.531), with the two compounds obtained in the factorial analysis and with oblique rotation. The internal consistency index is acceptable for the questionnaire, and this also reinforces the consideration of the general factor of personality as a unit construct.
We consider that the general factor of personality is the genuine basic trait of personality which combines the other traits. This is verified by observing the structure of the relationships obtained by checking the general factor against the models with 5 traits (Costa & McCrae, 1992; Harary & Donahue, 1994), with 3 traits (the EPQ; Eysenck & Eysenck, 1985) and with 2 (the SPSRQ; Torrubia et al., 2001).
So the GFP is related significantly with all the big five factors: positively with Extraversion and Openness, and negatively with Neuroticism, Agreeableness and Conscientiousness. This result is different of the one obtained in other studies that propose a general factor of personality in the five-factor model (Figueredo et al., 2006; Musek, 2007; Rushton, Bons and Hur, 2008). This discrepancy will be discussed below. Also, the GFP correlates positively and significantly with the "Approach" dimensions, such as E (Extraversion) and P (Psychoticism) of the EPQ, and SR (Sensitivity to Reward) of the SPSRQ. Conversely, the GFP correlates negatively and significantly with the "Avoidance" or "Inhibition" dimensions, such as N (Neuroticism) of the EPQ and SP (Sensitivity to Punishment) of the SPSRQ. Besides, the GFP also correlates positively and significantly with the sensation seeking of the SSS, as expected, which is considered an "Approach" dimension.
On the other hand, the GFP is a predictor of psychopathology. In principle, it is stressed that it correlates negatively and significantly with the personality disorders of the anxiety spectrum, such as the obsessive-compulsive disorder, the dependent disorder and the avoidance disorder. It also correlates negatively and significantly with emotional disorders in relation to anxiety and depression.
Furthermore, it is negatively and significantly related with serious personality disorders such as schizoid and schizotypical disorders. Therefore, a high score in the GFP represents an element of "protection" in relation to psychopathology, although it is positively related with the antisocial personality disorder, which is an extreme aspect of the "Approach" dimension. This correlation is not obtained in other studies (Rushton & Irwing, 2009d).
Rushton et al. (2008, 2009) consider as well defined the positive and negative poles of the GFP. Individuals high on the GFP possess more cooperative and prosocial personalities, and they have been characterized as altruistic, intellectually open, conscientious, outgoing, agreeable, extraverted, emotionally stable, intelligent and leaders, with high levels of well-being, satisfaction with life, self-esteem and emotional intelligence. So, the GFP would result from natural selection for socially desirable behavior. They left more progeny than those at the negative pole, since people prefer as mates, fellow workers and leaders those who are agreeable and emotionally stable (Figueredo & Rusthon, 2009). Figueredo et al. (2006) obtained significant negative correlations between Mini-K and measures of social deviance as delinquency, risk taking and impulsivity. Also, Mini-K correlated with altruism and intelligence (Rushton, Vernon & Bons, 2007). Rushton et al. (2008) predict that those with high scores on the GFP may have higher levels of emotional intelligence whereas those with low scores may more likely suffer from a personality disorder. Rushton and Irwing (2009a) found the emergence of a general factor of mental disorder based on the MMPI-2, that is negatively related with GFP. Also, Rushton & Irwing (2009d) extracted a General Factor of Personality from Millon Clinical Multiaxial Inventory-III, the Dimensional Assessment of Personality Pathology and the Personality Assessment Inventory. A GFP occupies the apex of the multifactorial hierarchy of personality disorders in the same way it has been found to do in the organization of non-clinic traits. The GFP accounted for high levels of variance in the three personality disorders scales. The authors claimed that the second-order factors could be interpreted as Internalization and Externalization.
The Unique Trait Personality Theory (Amigo, 2005) does not predict that all of traits of the General Factor of Personality are "desirable". This theory predicts that GFP is related with social deviance traits. In one study (Amigo et al., 2008) a proposal was made, indicating that Sensation Seeking is a good psychometric approach to one GFP. In this sense, it is interesting to highlight the relationships found among the SSS, and the Big Three and the Big Two.
The SSS total score strongly and positively correlated with the BAS in both sexes and displayed moderate negative correlations with the BIS (Torrubia et al., 2001). Zuckerman (1979) hypothesized that sensation seeking was related to Gray's reward sensibility but not to punishment sensibility. It is consistent with Zuckerman's prediction about the relationship between the EPQ and SSS scales. The SSS correlates positively with both E and P, but not with N (Zuckerman et al., 1978).
Some authors have related risk-taking behavior to underactive BIS (Fowles, 1987; Lykken, 1982), and have suggested a negative correlation between punishment expectancy and the SSS (Ball & Zuckerman, 1990). MacAndrew & Steele (1991) defined the BIS as a tendency towards anxiety, dread, avoidance of uncertainty and fear, and constructed a BIS scale which discriminated between psychiatric patients with medical histories of anxiety and panic attacks, and convict prostitutes who presented high-risk behavioral patterns in relation to sex and drugs. The BIS correlated positively with the Neuroticism scale and negatively with the Extraversion Scale of the EPQ.
These relations between "approach" traits, social deviance traits, and the GFP have been obtained in this study as have been described upwards.
The GFP may be understood to be a dimension between two extreme poles: extraversion and introversion. We can classify the subjects, with a cluster analysis, into two groups which correspond to extraversion and introversion. The two groups differ significantly with regard to the unique trait scores obtained (t = -8.49; p <.001).
However, what is the nature of the unique personality trait? The GFPQ is made up of two scales: the Extraversion scale (ES) and the Introversion scale (IS). The first refers to seeking stimuli, to the approach behavior. It is reflected in the items which make up the scale. Thus some items exist which refer to the intensity of the stimulus ("I like speed", "I like listening to music with the volume full up"); some refer to the pleasure found in the variety of stimuli ("I like to discover new places, difference settings, changes of places"); to novelty seeking ("I very much enjoy going on adventures, without planning anything", "I am always on the lookout for new, exciting experiences"); or they refer to behaviors that involve risks or excess ("I like activities involving risks, even if they are dangerous", "I like getting out of control and being a brute").
In relation to the Introversion Scale, it has items referring to avoidance ("I frequently seek others' protection"); to fears ("I am shy", "I'm a apprehensive person with all kinds of fears"); to feeling startled ("I often feel startled and afraid"); to novelty producing discomfort ("I don't like changes in my life as they make me feel insecure"); or to a high level of stress ("I worry about everything easily", "I am a sickly person").
Just as we have been explaining, the GFP or unique personality trait therefore constitutes a dimension related to the organism's interaction with environmental stimuli, one that ranges from the seeking behavior and the approach behavior in relation to stimuli (similar to approach dimension of Zuckerman, 1979 and Gray, 1987), to the extreme behavior of avoidance and having negative emotional reactions as a result of the environment. This is the basic dimension upon which the complete personality is built: the fundamental relationship between the organism and the environment.
As we cited above, also a psychometric approach to assess the general factor of personality has been proposed from Life History Theory, obtaining the K-Factor (Bogaert & Rushton, 1989; Figueredo et al. 2006). But, there are important differences between this instruments and the one presented here. This instrument has been constructed to measure the K-Factor. The GFP is assessed from scales for the "Big Five" factors of personality from MIDUS' scales. They were not constructed as a genuine and specific instrument to measure the GFP. However, the underlying theory is different. These psychometric instruments are, in general, constituted by aggregated variables including a variety of life-history parameters like an assortment of sexual, reproductive, parental, familiar and social behaviors. Figueredo et al. (2006) also developed a 20-item Mini-K in which people respond to items as "I am often in social contact with my blood relatives", "I am often in social contact of my friends" or "I have a close and warm relationship with my own children". The GFPQ, as we have seen, uses items about its foundational theory: the basic mechanism of response to external stimuli. However, this theory can be interpreted from an integrative model of evolutionary psychology. It is possible and desirable an approach between these theories that postulated a general factor of personality.
A provisional conclusion could be that the two poles of the general factor of personality correspond to Extraversion and Neuroticism. That is because Carver et al. (2000) propose a theoretical re-conceptualization and integration to understand their two basic factors (Approach and Avoidance) in terms of Extraversion and Introversion. Nevertheless, such solution does not seem to be a good solution because starting from a three-factor theory such as that of Eysenck, Psychoticism cannot be included neither inside Extraversion nor inside Introversion. Extraversion is related, primarily, with the positive reactivity to social stimuli (Sociability), while Psychoticism is related, primarily, with impulsivity and aggressiveness. Furthermore, Extraversion and Neuroticism are basic factors (non pathological) so in Eysenck's theory as in the theory of Costa & McCrae. The GFP is a bipolar dimension which the left pole is named Extraversion and the right pole is named Introversion but, in this case, Extraversion includes Sociability as well as Psychoticism and also includes pathological tendencies such as the antisocial personality disorder. That is because the sense here done to Extraversion is wider than the one given by other personality models. Besides, Introversion here includes Neuroticism as well as Anxiety, Sensitivity to Punishment and pathological tendencies such as personality disorders of fearful type.
Therefore, naming Extraversion to the GFP, it is possible to say that it presents two poles that could be identified with the Approach and Avoidance temperaments (Carver et al., 2000) and that integrate the different systems of action and emotion of the human being. In other words, the mentioned opposed temperaments would be, from the GFP perspective, two related behavior tendencies, two poles of the same dimension.
However, it is necessary to also bear in mind that this study has its considerations and limitations. Although one of the advantages of the study is to use a heterogeneous sample, which differs considerably in terms of age and profession (students and professionals), this study has been totally confined to a Spanish sample. It would be useful to extend the sample to other populations living in different geographical areas.
Besides, a unique personality trait score cannot substitute a broader description of personality. This broader description must consider the personality traits of the models with 3 or 5 factors. However, the score obtained in the UPTQ, along with the management of other questionnaires, will contribute to a more coherent and overall description of personality.
By way of conclusion, this study has proved encouraging in the sense that it counts on a general factor of personality which provides us with an overall vision of personality. In this sense, this study is one of the firsts of its kind (the first in Spain), to date (others are, for instance, Musek, 2007; Rushton et al., 2008; Rushton & Irwing, 2008), and one of the main results is the GFPQ, an instrument which constitutes a first psychometric approach to the idea of using a reliable and valid measurement of the General Factor of Personality.
Received February 19, 2009
Revision received December 14, 2009
Accepted December 18, 2009
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Salvador Amigo (1), Antonio Caselles (1), and Joan C. Mico (2)
(1) Universitat de Valencia (Spain)
(2) Universitat Politecnica de Valencia (Spain)
Correspondence concerning this article should be addressed to Salvador Amigo. Departamento de Personalidad, Evaluacion y Tratamientos Psicologicos. Universidad de Valencia. Av. Blasco Ibanez, 21. 46010 Valencia. (Spain). Phone: +34- 963864476. Fax: +34-963864669. E-mail: Salvador.Amigo@uv.es
TABLE 1 Structure Matrix of the GFPQ's items (ES: items from 1 to 10; IS: items from 11 to 20) Component 1 2 1. I like speed -.26 .57 2. I like listening to music with the volume full up .01 .46 3. I like trying drugs and feeling "high" -.04 .51 4. I like activities involving risks, even if they are -.36 .70 dangerous 5. I like discovering new places, different settings, -.27 .51 changes of place 6. I enjoy myself and I find it easy to "pull" and to -.15 .48 sexually seduce 7. I very much enjoy going on adventures without -.27 .56 planning anything 8. I like getting out of control and being a brute -.05 .58 9. I like places that are bustling, with a lot of -.12 .61 atmosphere 10. I am always on the look out for new, exciting -.09 .65 experiences 11. I worry about everything easily .65 -.23 12. I frequently seek others' protection .61 -.01 13. I often feel startled and afraid .65 -.07 14. I am a sickly person with frequent body symptoms .45 -.05 (headaches, rapid heartbeat, etc.) 15. I am shy .37 -.28 16. Normally, worries disturb my sleep .54 -.15 17. I am afraid of making a fool of myself .65 -.27 18. I take a long time to get over the "hard times" in .56 -.14 life 19. I'm a apprehensive person with all kinds of fears .62 -.11 20. I don't like changes in my life as they make me .45 -.25 feel insecure TABLE 2 Main descriptive statistics and age and sex comparisons (Student t-tests) N M SD t Sig. Sex Males 90 63.34 9.54 3.60 .000 Females 161 58.63 10.08 Age > 30 114 57.95 9.02 -3.27 .001 < 30 137 62.19 10.07 Table 3 Regression analysis Dependent variable: GFPQ. Predictors: The Big Five Variables Beta t Sig. Constant 11.79 .000 Extraversion .37 7.19 .000 Neuroticism -.47 -8.91 .000 Agreeableness -.15 -2.85 .005 Conscientiousness -.14 -2.82 .005 Openness .16 3.09 .002 ANOVA: F = 32.28 (p < .001). Adjusted R Square: .38 Table 4 Factor Analysis of the Big Five factors Component Extraversion .56 Neuroticism -.63 Agreeableness .68 Conscientiousness .50 Openness .54 Table 5 Intercorrelations between the General Factor of Personality Questionnaire (GFPQ), the Sensitivity to Punishment and Sensitivity to Reward Questionnaire (SPSRQ), the Eysenck Personality Questionnaire (EPQ) and the Sensation Seeking Scale (SSS) GFPQ SSS E N P SR SSS .58 ** E .35 ** .18 * N -.42 ** .06 -.15 * P .19 ** .30 ** -.05 .05 SR .23 ** .44 ** .24 ** .21 ** .09 SP -.58 ** -.08 -.36 ** .53 ** -.06 .10 E, Extraversion; N, Neuroticism; P, Psychoticism; SR, Sensitivity to Reward; SP, Sensitivity to Punishment. **. Correlation is significant at the .01 level (2-tailed) *. Correlation is significant at the .05 level (2-tailed) Table 6 Intercorrelations between the GFPQ, Anxiety, Depression and Hostility. Scales of SCL-90-R GFPQ Anxiety Depression Anxiety -.28 ** Depression -.34 ** .73 ** Hostility -.10 .56 ** .59 ** **. Correlation is significant at the .01 level (2-tailed) *. Correlation is significant at the .05 level (2-tailed) Table 7 Initial Cluster Centres Cluster 1 2 E 0 12 N 10 0 P 2 8 Table 8 Final Cluster Centres Cluster 1 2 E 7 9 N 8 2 P 3 3
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|Author:||Amigo, Salvador; Caselles, Antonio; Mico, Joan C.|
|Publication:||Spanish Journal of Psychology|
|Date:||Jan 1, 2010|
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