NADD Bulletin Volume X Number 2 Article 2

Complete listing

Assessment Of Personality And Social Competence In Persons With Dual Disabilities

Arno Willems, M.S.
MFCG at Koraalgroep

At the MFCG-Center in the Netherlands, a team of specialist-consultants including a psychiatrist, a psychologist, a social-psychiatric nurse-practitioner and a case-manager use a multi-dimensional model in the assessment of persons with intellectual disabilities and behavioral or psychiatric problems. Most of these individuals live in group homes or institutions. These dimensions encompass the four most salient factors known to contribute in the etiology and continuance of these problems. The first dimension is physical-medical factors, including syndromes or diseases. The second dimension is intra-psychic factors, such as intelligence, cognitive factors, adaptive competences, neuropsychological factors, social competence, and personality. The third dimension is interaction, education or staff behavior factors. The fourth dimension includes environmental-situational factors (e.g., living and work environment, cultural aspects, or school). All these factors are known to be possible instigating (triggering or contributing) conditions and/or vulnerability conditions for problem behavior (Griffiths, Gardner, & Nugent, 1997). This article will limit consideration to psychological factors. The physical-medical factors are addressed by the psychiatrist. The environmental factors are handled mostly by the social-psychiatric nurse-practitioner. Furthermore, the international literature base presents much expert- and evidence based knowledge about the analysis of problem behavior itself from a behavior-theoretical point of view.

Kraijer and Plas (2006) offer an excellent state-of-the-art handbook concerning assessment for persons with intellectual disability. Intra-psychic factors such as intelligence, adaptive behavior and neuropsychological factors are very well covered. Another topic that can be an instigating condition for problem behavior is staff behavior; so the assessment of this is important. Therefore, a self-report-instrument on interactive style aspects (IALB) has been constructed (Willems & Van der Heijden, 2004), but further validity and reliability studies of this instrument need to be done. The 3 factors in this instrument are:  (a) respectful attitude, (b) control-dominance, and affiliation dimensions (based on Leary [1957], Benjamin [2003] and on Transactional Analysis-aspects), and (c) coping style. It can be concluded that of all these instigating factors, there is especially a high need for guidelines and instruments for the assessment of personality and social competence in persons with intellectual disability. In this article there will be an in-depth presentation of these two dimensions, which can be considered to be essential in mental health and psychopathology.

To accomplish this, first a literature review is presented of both general psychological literature and intellectual disability literature on the core factors of personality and social competence in normal development. The focus was on literature in which the important domains and traits considered to be essential in personality disorders were described (e.g. Livesley, 2003; Cloninger, 2000; Eurelings-Bontekoe & Snellen, 2003). Special interest is given to take into account factors that not only can be measured in persons with mild and moderate intellectual disability, but also in persons with severe and profound intellectual disability.

The intention of this article is to present some integrative theoretical models and a practical guide concerning the following topics: (a) basic concepts of assessment, including phenomenological classification and diagnosis versus structural and developmental assessment; (b) structural domains, core factors of personality, and  appropriate assessment instruments; (c) structural domains and factors of social competence, and appropriate assessment instruments; (d) developmental phase models (Greenspan, 1989; Došen, 1993; Abraham, 1997); and (e) practical assessment guide through all this in 5 steps, combined with classifying models (e.g. DSM-IV, DC:0-3, DM-ID, RDC-PA, DCLD).

Basic Concepts

In persons with dual disabilities there are always symptoms and complaints which can be looked upon with descriptive, classifying, phenomenological and nomothetical assessment, like DSM-IV or ICD-10. This can be considered as the first and horizontal line of assessment, focusing upon symptoms and behavioral problems, and leading to a diagnosis. This gives many advantages, such as uniformity in communication about disorders; but there are disadvantages as well; a diagnosis gives no insight into etiology and causes, and most people can be better described in more-or-less than in all-or-nothing on the dimension between normality and disorder. Therefore, as many distinguished authors before (e.g., Greenspan, 1989; Došen, 2005; Eurelings-Bontekoe & Snellen, 2003, Oudshoorn et al., 1995), in this article I propose to take a structural and multidimensional perspective as an important supplement to the phenomenological, classifying and descriptive perspective as used in DSM-IV, DCLD (2001), Practice Guidelines (Deb, Matthews, Holt, & Bouras, 2001) and the upcoming DM-ID (NADD, in press). This could be considered as the second and vertical line of assessment. Here the most important domains and factors will be reviewed that are known in the literature on normal personality and social competence.

One could also start off by looking at the abnormal development, as most persons we support have severe behavioral and psychiatric problems; again a review has been carried out regarding the literature on personality disorders. Doing so, it is clear that much commendable effort is being made to adapt and modify the DSM-IV criteria to make them compatible for use with  persons with intellectual disability; as in the DCLD, Practice Guidelines, and DM-ID. As stated in the DM-ID (NADD, in press) it is important that the DSM-IV-TR-criteria for disorders such as personality disorders should be modified, taking into account the cognitive-developmental level of the intellectual disability, and that a personality disorder may be very difficult to diagnose in persons with profound or severe intellectual disability.

In this article, I propose to explore another route which could be much more productive; to not only adapt the criteria for DSM-disorders, but try to determine the more universal and essential factors in personality and social competence which can be assessed in all persons, including those with an intellectual disability. So here a more comprehensive contribution from psychology is presented in such a way that together with psychiatry one could determine if there is a sufficiently significant difference in the personality and social competence factors that one can consider them symptoms of a disorder.

Especially in working with persons with profound or severe intellectual disability, both psychologists and psychiatrists have difficulties in assessment and diagnosis. We must consider which disorders can be objectively determined and what can be said about personality development. One of the more fruitful solutions to this problem seems to be to take a strong developmental line of assessment; as in developmental psychopathology (e.g. Cichetti & Cohen, 1995), Developmental, Individual-Difference, Relationship-Based model (DIR) (Greenspan, 1989), Psychodynamic developmental model (Došen, 1983, 2005), Developmental Profile (Abraham, 1997), or in using infant and child psychiatry models (DC:0-3, RDC-PA). These models focus on the early development between 0-6 years. While the life experience of older persons with profound-severe-moderate intellectual disability is very different than those of younger persons, because of the cognitive levels these developmental models can be very useful for comparison in some respects.

Another more fundamental reason for taking this third line of assessment (a developmental and transactional perspective) can be found in the fact that a person is never static and that it is important to understand the dynamics of his or her development which have led to the current behavior and functioning. Therefore, a first attempt will be made to combine the aforementioned developmental phase-models of Greenspan, Došen and Abraham with the classifying models used by psychiatrists.

A Structural Model Of Personality

In order to understand personality, one has to have thorough knowledge of multiple theoretical models such as cognitive theories, psychodynamic theories, attachment-theory, trait-theories, and coping theories. Authors such as Eurelings-Bontekoe (2003) and Livesley (2003) are very convincing in stating that one has to use a multi-dimensional model in assessment of personality and personality disorders; even more so, their models include almost the same dimensions: symptoms, trait constellations, character, interpersonal factors, situational factors, cognitive schemata, and attachment. Focusing on literature on personality disorders, there is evidence that personality disorders can be understood from the dimensional perspective of the 30 facets of the Five-Factor-Model (Lynam & Widiger, 2001). Saulsman and Page’s meta-analysis (2004) showed even that each personality disorder displays a five-factor model profile that is meaningful. In this section on personality, several international and Dutch studies can be mentioned: Rothbart (2001), Cloninger (2000), Eurelings-Bontekoe and Snellen (2003),  Barelds (2003), Verheul (2005), Siever and Davies (1991), Blok, Berg and Feij (1990), and the “Big-5” literature, Livesley (2003), Zigler and Bennett-Gates (1999), Reiss and Havercamp (1998), and Abraham (1997).

In an attempt to integrate all these, a model on personality is suggested with 4 core domains: (a) temperament, (b) personality traits, (c) character, and (d) motives/drives. The 2 remaining domains which can be identified in this literature are cognitive styles and coping styles. Because they are only measurable at mild ID-level or higher, they will be included in the developmental phase models.

Correlations between these factors can be given, some quite robust, some more tentative. The proposition that is made here is that the first 3 domains of temperament, traits and character can be seen as one cluster of personality domains with 6 associated factors that can even be assessed in persons with profound and severe intellectual disability: These include (a) extraversion, surgency, Behavioral Activating System, novelty seeking; (b) introversion, Behavioral Inhibiting System, harm avoidance, inhibitedness; (c) agreeableness, reward dependence, low dissocial behavior, low egoism; (d) neuroticism, emotional dysregulation, affective instability, negative affectivity; (e) conscientiousness, persistence, compulsivity, effortful control; and (f) openness to experience. Some appropriate instruments which can be used are: NEO-PI-R and NEO-FFI (Costa & McCrae, 1992; Dutch version in 1996); Temperament and Character Inventory (TCI)(Cloninger, Svrakic & Przybeck, 1993; Dutch version in 1997); Temperament Vragenlijst voor Zwakzinningen (TVZ; Blok, van den Berg & Feij, 1990). The fourth domain on motives/drives can be measured at severe-moderate ID-levels and higher with e.g. EZ-Yale PQ (Zigler & Bennet-Gates, 1999) and the Reiss Profile MR/DD (Reiss & Havercamp, 2001).


A Structural Model Of Social Competence

Livesley (2003) reviews the clinical literature on personality disorders and concludes that  personality disorder involves two related problems: severe and chronic difficulties with interpersonal relationships, and problems with a sense of self or identity. Especially in persons with profound and severe intellectual disability, it will be difficult to assess directly aspects of identity or sense of self; but it seems that most of these problems are related to issues of trust, cooperation, attachment, intimacy and control (interpersonal factors), and these can be seen and assessed in a much easier way by looking at their interpersonal behavior and maladaptive interpersonal patterns instead of asking how they think about their selves. As for social competence, two domains are proposed: (a) attachment styles (secure-stable, avoidant-anxious, ambivalent-resistant, disorganized), and (b) interaction styles, based on dimensions of control and affiliation. Attachment styles can be measured by: Adult Attachment Interview (AAI; Main & Goldwyn, 1994; Dutch version is Gehechtheids Biografisch Interview, GBI); Parental Bonding Instrument (PBI; Parker, Tupling & Brown, 1979); Attachment Q-Sort (AQS; Waters & Deane, 1985); Brief Attachment Screening Questionnaire (BASQ; Bakermans-Kranenburg, Willemsen-Swinkels & Van IJzendoorn, 2003). Interaction styles can be best measured by: Structural Analysis of Social Behavior (SASB; Benjamin, 1996); Leary’s Interpersonal Circle (Leary, 1957); Interpersonal Adjective Scale-Revised (IAS-R; Wiggins, Trapnell & Phillips, 1988); Nederlandse Interpersoonlijke Adjectieven-Schalen (NIAS; Schacht & Rouckhout, 2005).

Developmental Phase Models

As stated earlier it is fundamental to take into consideration a developmental and transactional perspective besides the horizontal-phenomenological and vertical-structural perspective. Such a developmental-psychiatric approach in diagnosis of psychopathology in persons with intellectual disability has been proven to be very important not so much in diagnostic labeling, but in an understanding of pathological mechanisms (Sroufe & Rutter, 1984; Došen, 1993), for example, of personality disorders (Cichetti & Cohen, 1995; Došen, 2005). There are several authors who have presented this kind of developmental models, based on classic theories of development; such as Greenspan (FEAS and DIR, 2001), Došen (1983), and Abraham (1997). In an attempt to integrate the 2 models of Došen’s developmental-dynamic model of socioemotional development and a part of Abraham’s Developmental Profile, the following table is presented.


Table 1. Correlations between phases in Došen and levels in Abraham.


Developmental ageDošenAbraham   

0-6 mths.Adaptation00. No-structure level   

6-18 mths.Socialization10. Fragmentation level   

18-36 mths.Individuation; accent on autonomy/self20. Egocentricity level   

18-36 mths.Individuation: accent on dependence30. Symbiotic level   

3-6/7 yrs.Identification phase40. Resistance level   

7-12 yrs.Ego-differentiation phase50. Rivalry level   

Adolescence and older60-90 levels  


Besides the correlations between Došen and Abraham, it would be a challenge to suggest several correlations between these two and the developmental phases (0-4 years) described by Greenspan (2001). Table 2 presents Greenspan’s six developmental stages.


Table 2. Greenspan’s six developmental stages


Age Range in MonthsDevelopmental State   

0-3Homeostasis; Self-Regulation and Interest in the World   

2-7Forming Relationships, Attachments, and Engagement   

3-10Two-Way Purposeful Communication; Somatopsychological Differentiation   

9-18Behavioral Organization, Problem-Solving, and Internalization; Complex Sense Of Self   

18-30Representational Capacity   

30-48Representational Differentiation; Building Logical Bridges between Ideas and Emotional Thinking 


In both of the above models a distinction can be made between these developmental (vertical) phases or levels, and also between several (horizontal) aspects or themes at each phase/level.


In both of the above models in Table 1 a distinction can be made between these developmental (vertical) phases or levels, and also between several (horizontal) aspects or themes at each phase/level. A useful integrative proposition and some appropriate instruments for measuring these themes are presented in Table 3.


Table 3. Developmental Themes in Personality and Social Competence


Developmental Themes In PersonalityDevelopmental Themes In Social Competence   


Reiss Profile MR/DD (Reiss & Havercamp, 2001)Relations With Adults:

Schema Questionnaire (Young, 1994; Dutch version: 1997)   


Pictorial Scale of Perceived Competence and Social Acceptance (PSPCSA; Harter, 2002); CBSK/A (Dutch version of Harter’s Perceived Competence Scale: Veerman, Straathof, Treffers, et al., 1997, 2002); Rosenberg Self-Esteem Scale (RSES)(Rosenberg, 2002); Relations With Peers:

Socialization-subscale of the Vineland Adaptive Behavior Scales (VABS; Sparrow, Balla & Cichetti, 1984; Dutch version: Vineland-Z: de Bildt & Kraijer, 2003/5)   

Coping-Thinking Or Defensive Styles:

Defense Style Questionnaire (DSQ-40; Andrews, Singh & Bond, 1993; Dutch version: DSQ-42; upcoming DSQ-60)(Social) Cognitions And Role Taking Or Reflective Functioning:

Nowicki-Strickland Locus of Control Scale (N-SLCS; Nowicki, 2002); Reflective Functioning Scale (RFS, Fonagy et al., 1998); Theory-of-Mind-test (TOM; Muris, Steerneman et al., 1999); SIT (Vijftigschild, Berger & Spaendonck, 1969)  

Coping-Acting Or Behavioral Styles:

Utrechtse Coping Lijst (Schreurs, Willige, Brosschot, Tellegen & Graus, 1993)Conscience Or Norms:

Washington University Sentence Completion Test of Ego Development (WUSCT; Loevinger, 1985;

Dutch version: ZALC (Westenberg, Drewes, Siebelink et al., 2002) 


Taken as a whole, one could make up a developmental chart for personality as well as for social competence by determining which developmental level a person has achieved on each of the above themes.

Practical Assessment Guide

How can all of this be used in the daily practice of assessment of persons with dual disabilities? A first step in assessment is to gather a multidisciplinary team of professionals who will concentrate on the current functioning of a person. The team should consider five areas. First, the symptoms and behavioral problems must be described and a Functional Assessment or Analysis of Problem Behavior must be completed. Second, physical-medical factors must be evaluation and taken into consideration. Third, an assessment of intelligence factors and adaptive competencies must be completed. Fourth, staff behavior toward the individual must be noted, with the most typical interactional styles of each staff member toward the person described. Fifth, the team must describe the important environmental factors.

The second step proposed is to make a structural assessment of personality on the 4 core domains (temperament, traits and character which are clustered; and motives/drives) and of social competence on the 2 core domains: attachment style and interactional style. The suggested instruments can be used in this step.

As a third step, it is equally important to concentrate on one’s developmental and life-history by taking a thorough anamnesis (or recollection) on at least 4 age-levels: infancy (0-3 years), preferably with a distinction between adaptation and socialization phase; pre-school age (3-5 years), preferably with a distinction between individuation and identification phase; school age; and adult age. The team must note the important/deviant aspects on the above 5 current-functioning points at each age-level and in doing so, determine which developmental levels (Došen or Abraham) the person has achieved on each of  the 4 personality and 4 social competence themes. Then, a developmental profile can be given, leading to the most typical phase/level a person has achieved.

As a fourth step, as psychologists working together with psychiatrists, one could use all the above information on symptoms, medical factors, intelligence and the profiles from both the structural charts (on personality and social competence) as well as the developmental chart, to reach a psychiatric diagnosis on axis I and II. In trying to give a psychiatric diagnosis for adults based on all this information, using the corresponding psychiatric classification systems as DC:0-3, RDC-PA and DSM-IV-TR, one could also give a possible retrospective diagnosis for each age-level. It will be very interesting to see in how far the new DM-ID can facilitate this classification process, perhaps most usable for mild ID. Perhaps it is most practical in persons with profound, severe or moderate intellectual disability to use only diagnostic categories from DC:0-3 and RDC-PA, because these correspond with their cognitive-developmental ages.

As a fifth step, in an Integrative Person profile, the structural and developmental profile information plus all the information on the other dimensions (e.g. intelligence, physical factors, staff behavior, environmental factors, functional analysis) can be used to explain the behavior and psychiatric problems. This then enables one to define which aspects one should focus on in treatment, care, and support, and to define clear treatment goals.


In this article some integrative models and a practical guide have been offered concerning both structural and developmental assessment of personality and social competence in persons with dual disabilities. Furthermore, by connecting these psychological models with psychiatric classification models, perhaps this constitutes an alternative way for persons with intellectual disability to define whether or not there is a psychiatric disorder, instead of only relying on adapting and modifying the general criteria in DSM-IV.

A suggestion that could be made is to describe each individual with dual diagnosis retrospectively across each developmental phase using the aforementioned personality and social factors so one can conclude which factors most probably have contributed to the etiology of later problems or disorders.

A suggestion for the field is to refine the prototypical profiles of the personality and social factors for each psychiatric disorder by using the suggested structural personality and social competence domains. Eurelings-Bontekoe and Snellen (2003), Cloninger (2000), Livesley (2003), Lynam and Widiger (2001), Saulsman and Page (2004) provides examples of how this could be done. Even if there is no real disorder identified, then by following this assessment procedure, one can at least describe the typical developmental level, the strengths and weaknesses of the personality structure and of the structure of social competence in the person with intellectual disability.



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