COMPARATIVE DIMENSIONAL APPROACH OF PERSONALITY DISORDERS THROUGH THE MODELS OF BIG FIVE AND BIG SEVEN

INTRODUCTION

Personality disorders (PD) have always constituted a major problem in psychiatry, because of the impact they have on our society. Understanding personality and its disorders helps us to develop much more sophisticated treatment guidelines and prophylactic measures. The DSM-IV diagnostic criteria for PD uses a categorical approach and this way is not much of a help in an individualized treatment strategy. This latter assumption led researchers adopt an opening towards dimensional approaches. Phenotypic trait personality models have a better precision in clinical settings then developmental personality models but are not useful to describe underlying intrapsychic processes(1). The Big five model is a phenotypic trait personality model which was developed to assess normal personality but being a dimensional model it can be used to assess pathological personality too. Although this model cannot be used to diagnose PD, low scores on agreeabilness and emotional stability can be a predictor of pathologic personality traits. A developmental personality model is the Big seven which was developed for normal and pathologic personality, thus it is useful in the diagnosis of PD. Deficiencies of the character, namely low scores on self- direction and cooperativeness prove the presence of a PD.(2)

OBJECTIVE
Our aim was to compare the dimensions of the big five theory with the dimensions of the seven factor model, in the hope of finding correlations between them, and this way strengthening the link between different dimensional models.

MATERIALAND METHODS
A group of patients(N= 44) from our Personality Disorders Register were included in this study. This register contains recorded data from patients diagnosed with PD between 2011 and 2014 at the Psychiatric Clinic II in Tirgu Mures.
In our study we used the data of two self-administered, paper-and-pencil tests: the Temperament and Character Inventory(TCI) and the Disposition (Openess)- E x t r a v e r s i o n – C o n s c i e n t i o u s n e s s – A g r e e a b i l n e s s – Emotional Stability(DECAS) Inventory.
Ethical rules regarding informed consent and confidentiality were applied. Data where processed using Microsoft Excel(Microsoft Corp., Redmond, WA, USA) and GraphPad InStat. Linear(Pearson) correlation test was used calculate the correlation between different dimensions.

RESULTS
Descriptive statistics
Summed scores of the item pools where examined for each dimension (Table 1, Table 2)

Table 1. The mean, standard deviation(SD) and normality test for the summed scores of the DECAS dimensions.

Table 2. The mean, standard deviation(SD) and normality test for the summed scores of the TCI factors. Sd- self-directed; Co- cooperative; St- self-transcendent; Ns- Novelty seeking; Ha- Harm avoidance; Rd- reward dependence; P- persistence

Dimensionality assessment
Table 3 shows the correlation coefficients(r) between the dimensions of TCI and DECAS.

Table 3. Correlations between the dimensions of TCI and DECAS; only significant correlations are shown; moderate and strong(r > 0.4 or r < -0.4) correlations in bold.
Sd- self-directed; Co- cooperative; St- self-transcendent; Ns- Novelty seeking; Ha- Harm avoidance; Rd- reward dependence; P- persistence; D- Disposition (Openess); E- Extraversion; C-Conscientiousness; A-Agreeabilness; S- Emotional Stability

 

DISCUSSIONS
Disposition
We have found no significant correlation between disposition and self-direction, cooperativeness and novelty seeking. The moderate positive correlation between disposition and self-transcendence can be explained if we analyse the facets of these dimensions. A person who is acquiescent, insightful, transpersonal, creative and spiritual will surely have opening for fantasy, aesthetics, feelings, actions, ideas and values. An interesting result is the moderate positive correlation between disposition and persistence. At first sight it is hard to explain this correlation. The question is how can we connect persistence and openness in the case of PD. The best example for a PD with high scores on persistence is the obsessive-compulsive PD (OCPD). The link between persistence and openness to values becomes obvious through this type of PD which has a hypertrophic superego.

Extraversion
This dimension of the Big five model is known to have high scores at PDs of cluster B and from the perspective of the Big seven model cluster B can be characterized with high scores of novelty-seeking, confirming the positive correlation we have found in our study. The negative correlation between extraversion and cooperativeness is also easy to understand through the cluster B PDs. The strong negative correlation between extraversion and harm avoidance can be understood through the cluster C PDs: persons who have high scores of warmth, gregariousness, assertiveness, activity, excitement- seeking and positive emotions will definitely have low scores on the facets of harm avoidance, namely this persons can be described as optimistic, daring, autgoing and energetic.
Conscientiousness
Our study has once again confirm the positive correlation between conscientiousness and persistence both having high scores in the case of an OCPD.
Agreeabilness
As we mentioned above PDs can be described as low scorers on agreeabilness and emotional stability from the perspective of the Big five model and low scorers on self- direction and cooperativeness from the perspective of the Big seven model. This fact made our study group expect positive correlations between these dimensions as we can see our study has confirmed these correlations finding positive correlation between agreeabilness and cooperativeness respective emotional Stability and self-direction. The moderate positive correlation between agreeabilness and harm avoidance can be explained through the component facets of these dimensions: altruist , modest, tender-minded, people are usually seen as fearful and shy.
Emotional Stability
Was find to be negatively correlated with harm avoidance in other words the opposite pole of emotional stability is positively correlated with the above mentioned Big seven factor. Persons who are described as anxious, depressive and vulnerable could be described as being pessimistic fearful, shy and fatigable.

CONCLUSIONS
The study confirms once again the value of the dimensional approach in understanding normal and pathologic personality.
The comparative comments of the dimensional evaluation places a premium on the diagnosis of PDs
Except emotional stability, self-transcendence correlates with all of the dimensions of the Big five model which was validated transculturally. Self-transcendence has a major role in understanding PDs in any socio-culture.

REFERENCES
1.Sadock BJ, Sadock VA. Kaplan and Sadock’s Comprehensive Textbook of Psychiatry, 9th Edition. New York: Lippincott Williams and Wilkins, 2009.
2.Cloninger C R. The temperament and character inventory (TCI): A guide to its development and use. St. Louis, MO: Center for Psychobiology of Personality: Washington University, 1994.

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