Part IV

Assessment

14

Methods and Current Issues in Dimensional Assessments of Personality Pathology

Chloe M. Evans, Trevor F. Williams, and Leonard J. Simms

The purpose of this chapter is to review the current state of the dimensional assessment of personality disorder (PD), which is part of a broader paradigm shift in how psychopathology in general is conceptualized and measured; this shift is referred to by Kotov and colleagues (2017) as the “quantitative classification movement” (see also a recent chapter by Williams & Simms, in press, who describe the quantitative classification paradigm in the context of traditional and alternative classification paradigms). Briefly, a quantitative-dimensional model conceptualizes psychopathology as lying on a continuum with normal psychological functioning, such that psychopathology is quantitatively, as opposed to qualitatively, different from psychological health. This movement has elevated empirical relations between symptoms over clinical intuitions, leading to models that reject traditional diagnoses and emphasize the continuity of psychological functioning

A dimensional classification schema is especially relevant to the domain of personality pathology for at least two reasons. First, there is extensive evidence that PD symptoms vary continuously between clinical samples and the general population, suggesting a shared, dimensional latent structure (e.g., Livesley, Schroeder, Jackson, & Jang, 1994). Second, a dimensional model would potentially ameliorate the well-documented limitations of the categorical model of PD in the various editions of the Diagnostic and Statistical Manual of Mental Disorders (DSM), such as excessive comorbidity, within-disorder heterogeneity, arbitrary disorder thresholds, and poor coverage of the full range of aberrant personality functioning (e.g., Clark, 2007). Simply treating the ten current categorical PD diagnoses as dimensional would not address the limitations in this second point (e.g., comorbidity); thus, researchers have begun to focus on well-supported PD trait and dysfunction models (Morey, Bender, & Skodol, 2013; Widiger & Trull, 2007). This shift to trait and dysfunction models has positioned PD researchers as leaders in the shift to a quantitative, dimensional model of psychopathology (Krueger, 2013).

We begin with a review of the most widely accepted and commonly used measures of maladaptive personality traits, as well as dimensional assessment measures of psychosocial dysfunction associated with these traits. Although there are many points of continuity among these measures, we structure our discussion around their differences, as this may illuminate areas for further research and discussion. Important differences among measures include theoretical origin, method of scale construction, degree of correspondence with well-known trait dimensions, attention received in the empirical literature, and degree of bipolarity (vs. unipolarity) of the underlying dimensions. We also consider the clinical utility of the reviewed measures.

In the second part of this chapter, we review some of the more contentious issues at the forefront of dimensional assessment of personality pathology. First, we discuss the current state of the empirical literature surrounding whether and how personality traits can be psychometrically distinguished from personality dysfunction. Second, we touch upon the incremental utility of adaptive trait assessment above and beyond maladaptive trait assessment in clinical contexts. Third, we explore the question of whether traits are maladaptive at one pole (i.e., maladaptively unipolar) or both poles (i.e., maladaptively bipolar). Fourth, we discuss the similarities and differences in facet-level structure across trait models, in contrast to the general agreement that can be found at the broader domain level. Finally, we argue that multi-method assessment is a crucial component of dimensional personality assessment, and suggest that divergence among sources is not problematic, but clinically useful.

Review of PD Trait Measures

The assessment of maladaptive personality traits has a long and rich history, as evidenced by the number of measures reviewed here. We have organized our discussion of these measures (as well as an accompanying summary presented in Table 14.1) around theoretical origin, resulting in three categories: (1) measures rooted directly in the Five-Factor Model (FFM), (2) maladaptive extensions of the FFM keyed to most traditional PDs, known collectively as the Five-Factor Model of Personality Disorder (FFM-PD), and (3) pathological personality trait measures.

Table 14.1Key features of dimensional assessments

Measure	Citations	Construction	Structure	Scales & Items	Scale Polarity	Response Options	Formats	Availability	Norms	Languages	Clinical Features
Five Factor Model
Five Factor Form	17	Created descriptive anchors for each FFM facet	FFM	5 Domains (6 facets each), 30 Facets (single-items)	Bipolar	5-point scale (maladaptive low to maladaptive high)	Full	http://stephaniesweatt.wixsite.com/okstateppl/projects	Community	English	b
Five Factor Model Score Sheet	13	Created descriptive anchors for each FFM facet	FFM	5 Domains (6 facets each), 30 Facets (single-items)	Bipolar	7-point scale (problematic, very low to problematic, very high)	Full	Few et al. (2010)	Outpatient	English	b
Structured Interview for the Five Factor Model of Personality	74	Developed and evaluated interview questions for each FFM facet	FFM	5 Domains (6 facets each), 30 Facets (4 items each)	Bipolar	3-point scale (0-absent, 1-present, no impairment, 2-present, impairment)	Full	Psychological Assessment Resources	Manual	English, French	a, b, c, d, and f
Five Factor Model of PD
Five Factor Borderline Inventory	32	Developed scales for BPD-relevant FFM facets	Untested	12 Facets (120 items)	Unipolar	5-point scale (disagree strongly to agree strongly)	Full and Short	http://stephaniesweatt.wixsite.com/okstateppl/projects	Community	English	b
FFOCI	25	Developed scales for OCPD-relevant FFM facets	Untested	12 Facets (120 items)	Unipolar	5-point scale (strongly disagree to strongly agree)	Full, Short	http://samppl.psych.purdue.edu/~dbsamuel/research.html	mTurk	English, Chinese	b, c
FFSI	32	Developed scales for STPD-relevant FFM facets	Untested	9 Facets (90 items)	Unipolar	5-point scale (strongly disagree to strongly agree)	Full	widiger@email.uky.edu	None	English	c
FFNI	44	Developed scales for NPD relevant FFM facets	Antagonism, Neuroticism, & Agentic Extraversion; Grandiose Narcissism & Vulnerable Narcissism	15 Facets (148 items)	Unipolar	5-point scale (strongly disagree to strongly agree)	Full, Informant, Short	http://psychology.uga.edu/directory/josh-miller	Student	English, Italian-Short Form (Fossati, Somma, Borroni, & Miller, 2017)	a, c
EPA	99	Developed scales for Psychopathy-relevant FFM facets	Antagonism, Emotional Stability, Disinhibition, & Narcissism	18 Facets (178 items)	Unipolar	5-point scale (disagree strongly to agree strongly)	Full, Short, Super Short	http://psychology.uga.edu/directory/josh-miller	None	English	a, c, and e
FFDI	24	Developed scales for DPD-relevant FFM facets	Untested	12 Facets (120 items)	Unipolar	5-point scale (strongly disagree to strongly agree)	Full	widiger@email.uky.edu	None	English	c
FFHI	11	Developed scales for HPD-relevant FFM facets	Untested	10 Facets (100 items)	Unipolar	Unknown	Full	widiger@email.uky.edu	None	English	-
FFAvA	12	Developed scales for AVPD-relevant FFM facets	Untested	10 Facets (70 items)	Unipolar	5-point scale (disagree strongly to agree strongly)	Full	dlynam@purdue.edu	None	English	-
Pathological Trait Models
SNAP-2	212	Content- and factor-analytic studies of PD criteria and related features	Negative Affectivity, Positive Affectivity, Disinhibition vs. Constraint	15 traits (390 items)	Mixed	True or False	Full, Short	Contact Lee Anna Clark, lclark6@nd.edu	Manuel	English	a, b, c, d, e, f
DAPP-BQ	264	Literature review, expert opinion, and interviews of PD clients	18 primary traits/dimensions	69 sub-traits (between two and seven per dimension)		5 pt-scale (Very Unlike Me to Very Like Me)	DAPP-BQ, DAPP-BQ-A, DAPP-BQ-SF, DAPP-DQ	http://www.sigmaassessmentsystems.com/assessments/dimensional-assessment-of-personality-pathology-basic-questionnaire/	Community, clinical	English, French, Spanish, Portuguese	a, b, c, d, e, f
MMPI PSY-5-RF	189	Replicated rational selection used to match item to theoretical constructs	Aggressiveness, Psychoticism, Disconstraint, Negative Emotionality, and Positive Emotionality	5 Domains (104 items)	Unipolar	True or False	MMPI-2 and MMPI-2-RF	University of Minnesota Press	Manual	English, Dutch, Chinese, Spanish, Arabic, Farsi, French, Greek, Hebrew, Hmong, Icelandic, Italian, Japanese, Korean, Norwegian, Russian, Thai, Turkish, Vietnamese	a, b, c, d, e, f
PID-5	336	PD trait literature review and bottom-up factor analyses	Negative Affectivity, Detachment, Psychoticism, Antagonism, and Disinhibition	25 Facets (220 items)	Unipolar	4-point scale (Very False of Often False to Very True or Often True)	Full, Short-100, Short-25, Informant, Child	https://www.psychiatry.org/psychiatrists/practice/dsm/educational-resources/assessment-measures	Community, Clinical	English, Dutch, Norwegian, German, Arabic, Portuguese, French, Spanish	a, b, c, d
CAT-PD	66	PD trait literature review and bottom-up factor analyses	Based on a PSY-5 organizing scheme	33 Facets (216 items + 30 for the optional validity scales)	Unipolar	5-point scale (Very Untrue of Me to Very True of Me	Full-Adaptive, Full-Static, Informant, Interview	Contact Len Simms, ljsimms@buffalo.edu		English, Dutch, Norwegian, Spanish	a, b, c, d, e
PAI (PID-5 scoring)	1	Stepwise regression using PAI scales as predictors of PID-5 facets	Negative Affectivity, Detachment, Psychoticism, Antagonism, and Disinhibition	25 Facets (344 items)	Unipolar	4-point scale (Not at all true to Very true)	Adult & Adolescent	https://www.parinc.com/products/pkey/287	Morey, 1991 and Busch et al., 2017	Spanish	a, b, e
General Personality Functioning
MDPF	39	Conceptual generation followed by 2 rounds of factor analysis	2 higher-order factors: non-coping, non-cooperativeness	10 items per each higher-order factor	NA	4-pt scale (definitely false – definitely true	Full only	Parker et al., 2004	Italian community sample	English, Italian (Fossati et al., 2017)	b, d
SIPP	101	Expert-guided rational-intuitive approach	5 higher-order domains: self-control, identity integration, relational capacities, social concordance, responsibility	16 lower order facets, between 2 and 5 facets per domain, between 7 and 8 items per facet	NA	4-pt (I fully agree, I partly agree, I partly disagree, I fully agree)	Full, Short Form (SIPP-SF 64 items)	https://www.deviersprong.nl/over-de-viersprong/over-de-viersprong-onderzoek/onderzoekslijn-diagnostiek/onderzoekslijn-assessment-en-indicatiestelling/sipp-main-menu/	PD, Outpatient, Community	English, Dutch, Norwegian, Argentinian, Italian	a, b, c, d, f
GAPD	8 citations for Hentschel & Livesley, 2013; 3 empirical studies prior to Hentschel & Livesley, 2013	Literature review, assessment interviews, and therapy sessions informed the writing of items to assess adaptive failure constructs	(1) Self-Pathology, (2) Interpersonal Dysfunction	original 114-item version shortened to 85-item version (Hentschel & Livesley, 2013). Only items that differentiated between criterion groups (PD vs. no PD) were retained. 8 subscales (4 self-pathology, 4 interpersonal pathology)		5-pt (1 = very unlike me – 5 = very like me)	Full only	Livesley (2006)	Canadian Community Sample & Dutch Clinical Sample	English, Dutch (Berghuis, 2007), German (Hentschel & Livesley, 2003)	b
LPFS-BF 2.0	None, but 7 for the original LPFS-BF	Conceptually generated by 4 clinical psychologists to capture LPFS. One item per facet	2 higher-order domains (self and interpersonal functioning); 4 subdomains (self: identity, self-direction; interpersonal: empathy, intimacy)	12 facets (3 per subdomain)		4-pt (1 = very false or often false, 4 = very true or often true)	self-report	Bach & Hutsebaut, 2018	Outpatient, inpatient	Dutch, English	a, c
LPFS-SR	0	Conceptually generated to capture LPFS. One item per clause	2 higher-order domains (self and interpersonal functioning); 4 subdomains (self: identity, self-direction; interpersonal: empathy, intimacy)	80 items		4-pt (1 = totally false, not at all true, 4 = very true)	self-report	Morey, 2017 supplemental material	MTurk sample	English	a, b, c, d
DLOPFQ	1	Experts individually conceptually generated items to assess the LPFS constructs. Items agreed upon among experts were retained	2 higher-order domains (self and interpersonal functioning); 4 subdomains (self: identity, self-direction; interpersonal: empathy, intimacy) 2 further subdomains per each subscale (Work/School and Social (close) Relationships)	132 items (66 questions asking about work/school contexts and the same 66 questions asking about Social Relationships context		6-pt Likert (1 = strongly disagree to 6 = strongly agree)	self-report	huprichst@udmercy.edu	Psychiatric and medical outpatient sample	English	a, c
IIP-64/IIP-C	512	Intake interviews, circumplex analysis (Alden et al., 1990), further psychometric pruning (final items chosen based on communalities and scale loadings	2 higher-order dimensions: (1) dominance, (2) nurturance	8 scales: Domineering (PA), Vindictive (BC), Cold (DE), Socially Avoidant (FG), Nonassertive (HI), Exploitable (JK), Overly Nurturant (LM), Intrusive (NO)		5-pt Likert scale (0 = not at all to 4 = extremely)	IIP-32 (Short Circumplex)	available for purchase at https://www.mindgarden.com/113-inventory-of-interpersonal-problems	Manual	English, Finnish, Greek, Malay, Polish, Spanish	a, b, c, f

Note: Citations are based on Web of Science searches from February-May of 2018. Clinical features are coded as follows: a = published factor structure, b = available norms, c = all scale alphas > .70, d = retest reliability evidence, e = presence of validity scales, and f = interpretive materials available (case studies, manuals, etc.).

Five Factor Model Measures

FFM measures do not assess pathological traits per se; rather, they are based on the assumption that extremely low or high levels of the five FFM normative-range personality traits – neuroticism, extraversion, agreeableness, conscientiousness, and openness – constitute personality pathology and are associated with psychosocial dysfunction. The FFM has its roots in two distinct traditions. First, any discussion of the FFM is incomplete if it fails to acknowledge the conceptual links between the FFM and the lexically-based Big Five literature (e.g., Goldberg, 1993). That said, clinical applications of the FFM largely have their roots in the work of Costa and McCrae, who formalized the FFM as the five broad traits listed above and their nested 30 subordinate facets. Although the NEO family of measures were designed to measure normal-range variants of personality, they deserve discussion in this section because the NEO has been the basis of a large literature linking FFM traits and personality pathology (e.g., Widiger, Trull, Clarkin, Sanderson, & Costa, 2002). The full NEO-FFM model first emerged in the revised NEO Personality Inventory (NEO-PI-R; Costa & McCrae, 1992). A minor revision was published in 2015 (NEO-PI-3; McCrae, Costa, & Martin, 2005; McCrae & Costa, 2010), but the NEO-FFM has remained remarkably consistent and robust for over 25 years. Notably, the work of Tom Widiger and his colleagues and students has greatly enhanced our understanding of PD traits, using the FFM model as a foundation. Most relevant to our purpose here, Widiger has developed several FFM-based measures designed to explicitly extend the normal-range NEO traits into the maladaptive range, presumably making them more amenable to clinical research and practice. We now discuss the most prominent of these FFM measures.

The Five Factor Form

The Five Factor Form (FFF; Rojas & Widiger, 2014) is a recent measure of the FFM designed to explicitly assess adaptively and maladaptively high and low levels of each FFM facet (Rojas & Widiger, 2018). The FFF consists of one item for each FFM facet, each rated on a five-point scale including the following anchors: 1 (maladaptive low), 2 (normal low), 3 (neutral), 4 (normal high), and 5 (maladaptive high). In addition, each item also includes exemplar descriptors of both the maladaptive and normal-range options. For example, for the facet of Warmth, 1 = “cold, distant” and 2 = “formal-reserved” on the low end, and 4 = “affectionate, warm” and 5 = “intense attachments” on the high end. Thus, options 1 and 5 reflect maladaptively low and high manifestations of warmth, respectively, whereas options 2 and 4 reflect normal-range variations in warmth. Although only limited research has been published on the FFF thus far, some early work has demonstrated evidence for its convergent and discriminant validity relative to a range of measures, including other FFM measures (e.g., Rojas & Widiger, 2018). That said, the explicit adaptive-maladaptive structure of the FFM has shown only mixed support thus far in the literature and deserves further scrutiny (Rojas, 2017).

The Five Factor Model Score Sheet

The Five Factor Model Score Sheet (FFMSS; Widiger & Spitzer, 2002) is a conceptually generated, brief clinician-rated measure of the FFM with one item per facet (Few et al., 2010). With respect to reliability of the FFMSS, there is empirical evidence for the adequate internal consistency of four of five FFMSS domains, with the exception of Neuroticism (α = .61; Few et al., 2010). With respect to validity, the FFMSS has demonstrated good convergence with maladaptive trait measures (e.g., the Schedule for Nonadaptive and Adaptive Personality [SNAP; Clark, 1993]) as well as expert-generated PD prototypes (Few et al., 2010). Further, the FFMSS demonstrated significant incremental validity relative to the DSM-IV PD criteria in the prediction of psychosocial dysfunction across domains (e.g., romantic relationships, occupational functioning; Few et al., 2010).

The Structured Interview for the Assessment of the Five-Factor Model of Personality (SIFFM)

The SIFFM (Trull & Widiger, 1997) is a semi-structured interview measure of the FFM whose 120 items are evenly distributed across the 30 NEO facets, such that there are four items per facet (Trull et al., 1998). The SIFFM was developed in hopes of capitalizing on the psychometric advantages of the interview method over self-report (e.g., allows for clinical observation, responses may be clarified by elicitation of examples; Trull et al., 1998). In addition, an interview measure presumably facilitates research examining the associations between personality traits and PDs, given that the PDs are commonly assessed via interview (Trull et al., 1998). The SIFFM fulfills many of our criteria for clinical utility (see Table 14.1 Note), including a published factor structure, acceptable internal consistency, and acceptable test-retest reliability (Trull et al., 1998). Further, the SIFFM domains converge in a theoretically predictable way with the NEO-PI-R and PID-5 domains, as well as peer ratings of FFM traits (Helle, Trull, Widiger, & Mullins-Sweatt, 2017; Trull et al., 1998). Finally, there is evidence that the SIFFM accounts for significant variance in PD symptoms after controlling for general personality pathology (Trull, Widiger, & Burr, 2001).

FFM-PD Measures

Eight measures are associated with the FFM-PD, one each corresponding to the DSM-5 Section II PDs, with the exception of Paranoid PD and Schizoid PD. The theoretical origin of these measures can ultimately be traced back to the FFM, but not as directly as the FFM measures reviewed above. Rather, these measures follow from an additional postulate that the FFM can account for the ten categorical PD diagnoses (e.g., Widiger et al., 2002). As such, the FFM-PD measures do not directly assess normative personality traits, nor are they intended to capture the full breadth of the FFM (i.e., assessing all five factors). Rather, each measure is limited to those facets of the FFM that have shown empirical relevance to a given PD based on extant research (e.g., Bagby & Widiger, 2018).

The number of facets per measure ranges from 9 for the Five Factor Schizotypal Inventory (FFSI; Edmundson, Lynam, Miller, Gore, & Widiger, 2011) to 18 for the Elemental Psychopathy Assessment (EPA; Lynam et al., 2011). Two FFM-PD measures – the Five Factor Narcissism Inventory (FFNI; Glover, Miller, Lynam, Crego, & Widiger, 2012) and the EPA – have a factor analytically derived domain-level structure, whereas the remainder of FFM-PD measures are scored and interpreted only at the facet level. Notably, neither the FFNI nor the EPA has a higher-order domain structure that is perfectly aligned with the FFM (see Table 14.1 for details). Thus, unlike the three FFM-derived measures described above, it is unclear how exactly the FFNI and EPA measures fit within the broader FFM framework and rich empirical tradition of the full FFM.

Space constraints do not permit a full description of each FFM-PD measure; interested readers are referred to a recent special issue of Psychological Assessment that focuses on the measures within this collection (Bagby & Widiger, 2018). However, it is notable that the FFM-PD measures vary in the extent to which they have been used in empirical research (citations ranging from 11 for the Five Factor Histrionic Inventory [FFHIl; Tomiatti, Gore, Lynam, Miller, & Widiger, 2012] to 99 for the EPA). In terms of clinical utility, these measures fulfill between zero (FFHI, Five Factor Avoidant Assessment) and three (EPA) of our clinical utility criteria. Moreover, it is unclear how this collection of measures is meant to be used in clinical work, since collectively these measures include too many items and numerous overlapping scales to be efficiently used by practicing clinicians. Work is needed to integrate these eight measures into a single, efficient FFM-PD measure.

Pathological Trait Model-Derived Measures

In contrast to the previously reviewed measures, some PD trait measures have been developed to directly assess the traits presumed to underlie the PD criteria listed in the various editions of the DSM. Such measures have emerged in the literature over the last 25 years, with increasing evidence of structural consensus and clinical utility.

Schedule for Nonadaptive and Adaptive Personality-2

The SNAP (Clark, 1993) and its second edition (SNAP-2; Clark, Simms, Wu, & Casillas, 2002) were developed to provide a means for assessing trait dimensions relevant to the diagnosis of personality pathology. The SNAP-2 includes 390 items and measures three broad temperament dimensions corresponding to a Big Three personality model (i.e., negative temperament, positive temperament, and disinhibition vs. constraint), as well as 12 lower-order facets that were developed via an iterative series of factor- and content-analytic procedures applied to PD diagnostic criteria and related features. The clinical utility of the measure is strong, as it includes a comprehensive set of validity scales (including a set of scales keyed to the DSM PDs for clinicians who desire a bridge between categorical and trait-dimensional PD conceptualizations), has strong community and clinical norms, and has considerable evidence in support of its reliability and validity (e.g., see Simms & Clark, 2006).

The Dimensional Assessment of Personality Pathology – Basic Questionnaire (DAPP-BQ)

The DAPP-BQ (Livesley & Jackson, 2009) is similar to the SNAP in that it was developed as an early attempt to represent and measure the traits presumably underlying personality pathology. The DAPP-BQ includes 290 items and measures 18 lower-order traits nested within 4 higher-order dimensions – Emotional Dysregulation, Dissocial Behavior, Inhibition, and Compulsivity. Items were conceptually generated to capture the DSM-III PD criteria (Bagge & Trull, 2003). All 18 of the DAPP-BQ trait scales have documented evidence of internal consistency across clinical and non-clinical samples, as well as test-retest reliability (e.g., van Kampen, 2002). Further, the DAPP-BQ has demonstrated convergent validity with respect to PD symptoms (e.g., Bagge & Trull, 2003) and normal-range personality traits (e.g., van Kampen, 2002). These features, as well as the existence of automated administration and interpretation services, make the DAPP-BQ a measure with reasonable clinical utility. However, the lack of validity scales arguably is a limitation of the DAPP-BQ in high-stakes testing contexts.

Personality Psychopathology Five MMPI-2-RF Scales (PSY-5)

The PSY-5 model (Harkness & McNulty, 1994, 2007) – which includes the five broad traits of Aggressiveness, Psychoticism, Constraint, Negative Emotionality, and Positive Emotionality – is notable because it represents both a measure of broad traits thought to be relevant to adaptive and maladaptive personality and a model of such traits that has gained traction in recent years as the basis for the alternative model of personality disorder (AMPD; as published in Section III of DSM-5) and numerous measures of AMPD traits (to be reviewed below). As a measure, the PSY-5 first appeared as a cohesive set of scales developed for the Minnesota Multiphasic Personality Inventory-2 (MMPI-2). More recently, the PSY-5 scales have been refined for the restructured forms of the MMPI-2 (MMPI-2-RF; Ben-Porath & Tellegen, 2008). Items initially were chosen from the full MMPI-2 item pool via replicated rational selection, followed by rational and psychometric pruning (Harkness, McNulty, & Ben-Porath, 1995). The scales have demonstrated good reliability, as well as convergent validity with respect to the PID-5 and various external criteria (e.g., Harkness et al., 2013). The PSY-5 scales have good clinical utility to the extent that they are embedded in a widely used and researched measure; thus, all of the features that make the MMPI-2-RF useful in clinical settings (e.g., strong norms, validity scales) can be applied to the PSY-5 scales. In addition to being a set of MMPI-2-RF scales, the PSY-5 model bears a strong resemblance to the structural model underlying the AMPD and its derivative measures described below. However, the lack of PSY-5 facet scales sets an upper limit on its usefulness.

Personality Inventory for DSM-5 (PID-5)

The PID-5 (Krueger, Derringer, Markon, Watson, & Skodol, 2012) is the official measure of the AMPD as represented in Section III of DSM-5. It includes 220 self-report items that assess the 25 maladaptive traits of the AMPD. Traits are distributed across five higher-order domains that are isomorphic with the PSY-5 model: Negative Affectivity, Detachment, Antagonism, Disinhibition, and Psychoticism (Krueger et al., 2012). Items were conceptually generated by expert consensus and psychometrically pruned over two rounds of data collection (Krueger et al., 2012). The PID-5 has demonstrated adequate to good convergent and discriminant validity with respect to normal-range trait measures, other maladaptive trait measures, and the traditional DSM-IV PD categories (e.g., Wright & Simms, 2014; Yam & Simms, 2014). Moreover, the measure has demonstrated adequate test-retest reliability and a replicable factor structure (e.g., Al-Dajani, Gralnick, & Bagby, 2016). The PID-5’s status as the official measure of the AMPD and its large research base are features that improve its clinical utility; however, the lack of integrated validity scales limits its usefulness in high-stakes contexts.

Personality Assessment Inventory PID-5 Scoring (PAI-PID-5)

The Personality Assessment Inventory (PAI; Morey, 1991) is a self-report measure consisting of 344 items nested within 22 full scales and 31 subscales that assess a broad range of psychopathology constructs, including personality pathology. Most relevant to the present chapter, Busch, Morey, and Hopwood (2017) published a scoring algorithm by which the PAI scale scores could be used to assess the AMPD traits via multiple regression. Results indicated that PAI-estimated AMPD traits were adequately correlated with PID-5-estimated AMPD trait profiles and reproduced the five factors of the AMPD with good fidelity (Busch et al., 2017). The primary advantage of using the PAI to estimate AMPD traits is that the PAI has a robust research literature and includes features that improve its clinical utility (e.g., strong norms and validity scales), thus making it more heavily used in clinical settings.

Comprehensive Assessment of Traits Relevant to Personality Disorder-Static Form (CAT-PD-SF)

The CAT-PD-SF (Simms et al., 2011) was developed to identify a comprehensive model and efficient measure of PD traits. Although developed independently, the CAT-PD facets are similar to those represented in the AMPD. The CAT-PD-SF is a brief measure drawn from the full CAT-PD item pool. The CAT-PD project yielded 33 facet scales measuring an integrative set of PD traits. These scales were formed following data collection through an iterative series of factor- and content-analytic procedures. The full CAT-PD scales are long by design (1366 total items; M scale length = 44 items ± 12) so as to be amenable for computerized adaptive testing. However, a static form (CAT-PD-SF) was developed using a combination of statistical and content validity considerations to facilitate quick and standardized assessment across studies and in clinical settings. The static form measures all 33 traits using 216 items. In addition, a 246-item version exists that includes validity scales. The static scales demonstrate good internal consistency, test-retest reliability, and evidence of convergent and discriminant validity (e.g., Wright & Simms, 2014), and have been used in a growing number of PD trait studies. Notably, the CAT-PD has been shown to tap additional variance relevant to PD not directly assessed by the PID-5, such as self-harm and antisocial behavior (e.g., Evans & Simms; 2018; Yalch & Hopwood, 2016).

Personality Dysfunction Measures

The assessment of personality dysfunction is a younger and less developed area of research than that of personality trait assessment (Ro & Clark, 2009). However, there has been an increased focus on conceptualizing and measuring personality dysfunction in recent years in the wake of the publication of DSM-5, particularly in response to AMPD’s inclusion of a clinician rating scale of self and interpersonal dysfunction (i.e., the Levels of Personality Functioning Scale [LPFS; APA, 2013]). Reviewed below (and summarized in Table 14.1) are seven prominent personality dysfunction measures, four of which predate the LPFS, and three of which have been developed with the express purpose of operationalizing the LPFS.

In addition, seven of the most prominent measures of impairment in personality functioning are included in Table 14.1. The theoretical origin, method of construction, and structure of each measure are reviewed below, and reliability and validity are briefly evaluated.

Inventory of Interpersonal Problems-Circumplex (IIP-64/IIP-C). The IIP-64 (Alden, Wiggins, & Pincus, 1990) is one of many adaptations of the original 127-item Inventory of Interpersonal Problems developed by Horowitz and colleagues in 1988 (see Hughes & Barkham, 2005, for a review). The IIP-64 most directly assesses interpersonal problems that characterize personality dysfunction, whereas the remaining measures assess both self and interpersonal problems. It consists of two higher-order dimensions (Dominance and Nurturance) and eight scales (Domineering, Vindictive, Cold, Socially Avoidant, Nonassertive, Exploitable, Overly Nurturant, and Intrusive).

Measure of Disordered Personality Functioning Scale (MDPF). The MDPF (Parker et al., 2004) is not linked to any particular theory of personality dysfunction; rather, the initial phase of item construction was informed by a comprehensive literature review (Parker et al., 2002) from which the research team identified 17 constructs central to the definition of personality dysfunction. The 141 items initially written to assess these constructs where whittled (via several rounds of factor analysis) to 20 items loading onto two higher-order factors: Non-Coping and Non-Cooperativeness, which refer to self and interpersonal dysfunction, respectively (Parker et al., 2004).

General Assessment of Personality Disorder (GAPD). The GAPD (Livesley, 2006) is an 85-item self-report measure intended to assess self and interpersonal pathology as defined by Livesley’s adaptive failure model of PD (Berghuis, Kamphuis, & Verheul, 2012). Its structure is hierarchical, such that eight subfacets are nested within two higher-order facets (i.e., Self Pathology and Interpersonal Pathology; Hentschel & Livesley, 2013). The four subfacets that load onto Self Pathology are Differentiation, Integration, Consequences of Self Pathology, and Self-Directedness (Hentschel & Livesley, 2013). The four subfacets that load onto Interpersonal Pathology are Attachment/Intimacy, Affiliation, Prosocial Behavior, and Cooperativeness. An initial 144-item pool was conceptually generated on the basis of both a literature review and therapy sessions with individuals with a PD (Hentschel & Livesley, 2013). Subsequently, items that failed to differentiate between individuals with and without a PD in pilot testing were eliminated (Hentschel & Livesley, 2013).

Severity Indices of Personality Problems (SIPP). The SIPP (Verheul et al., 2008) is a 118-item self-report measure that was developed using an expert-guided, rational-intuitive approach to measure five higher-order domains of personality functioning: Self-Control, Identity Integration, Relational Capacities, Social Concordance, and Responsibility (Verheul et al., 2008). However, it is important to note that four of the five higher-order domains seem to correspond with the four subdomains of the Levels of Personality Functioning Scale (LPFS) described in the AMPD in DSM-5. Specifically, SIPP Self-Control is conceptually consistent with LPFS Self-Direction, SIPP Identity Integration maps onto LPFS Identity, SIPP Relational Capacities maps onto LPFS Intimacy, and SIPP Social Concordance is conceptually similar to LPFS Empathy. There is considerable evidence for the clinical readiness of the SIPP-118, including a replicated factor structure and adequate test-retest reliability, internal consistency, and convergent and discriminant validity (see Verheul et al., 2008, for more details).

LPFS-Based Measures. All three measures reviewed below share the factor structure of the LPFS, with four lower-order domains (Identity, Self-Direction, Empathy, Intimacy) that are nested within two higher-order domains (i.e., Identity and Self-Direction onto Self-Functioning, and Empathy and Intimacy onto Interpersonal Functioning).

Levels of Personality Functioning Scale – Brief Form 2.0 (LPFS-BF 2.0). The LPFS-BF 2.0 (Bach & Hutsebaut, 2018) was developed as a PD screen by a team of four clinicians, and consists of 12 items corresponding to each of the 12 LPFS scoring criteria (Hutsebaut, Feenstra, & Kamphuis, 2016). Among several of its strengths are the wide availability of the LPFS-BF-2.0 and empirical support for its convergent validity (e.g., LFPS-BF Self-Functioning is associated with SIPP Identity Integration, LPFS Interpersonal Functioning is associated with SIPP Relational Capacities and Social Concordance; Hutsebaut et al., 2016). Further, there is empirical support for the utility of the LPFS-BF in differentiating those with versus without PDs in a clinical sample (Hutsebaut et al., 2016).

Level of Personality Functioning Scale – Self-Report (LPFS-SR). The LPFS-SR (Morey, 2017), an 80-item measure developed by Les Morey, consists of one item per “information unit” in the LPFS scoring criteria. One unique aspect of this measure is that its scoring scheme weighs items according to the LPFS severity level to which they correspond, such that items that reflect moderate impairment are weighted +1.5, whereas items that reflect severe impairment are weighted +2.5 (Morey, 2017). One particular strength of the LPFS-SR is its high level of test-retest reliability, albeit over a relatively short time interval (i.e., approximately 15 days). Hopwood, Good, and Morey (2018) reported test-retest reliabilities of .90, .89, and .91 for self-functioning, interpersonal functioning, and the total score, respectively.

DSM-5 Levels of Personality Functioning Questionnaire (DLOPFQ). The DLOPFQ (Huprich et al., 2018) was developed from a larger pool of items written independently by experts to assess the constructs underlying the LPFS; the final 66 items were those agreed upon by the experts as a team (Huprich et al., 2018). Each of the 66 items is asked twice; respondents are asked to report on how true each item is for them in the context of work/school and then in the context of social relationships (Huprich et al., 2018). Explicit consideration of cross-situational variability is a potential unique strength of the DLOPFQ; however, Huprich and colleagues (2018) failed to detect meaningful cross-situational differences in item responses in a mixed sample, calling into question the utility of this distinction.

Current Topics in Dimensional Assessment of Personality Pathology

Can Traits and Dysfunction Be Distinguished?

Despite the existence of separate measures to assess PD traits and personality dysfunction, as described above, recent literature has openly questioned whether such traits and impairments are psychometrically differentiable (see Widiger et al., 2019, for a review). There are a number of reasons why researchers and clinicians may wish to assess personality traits separately from dysfunction. First, one might argue that PD assessment should be consistent with the PD diagnostic system, in which extreme traits/features and psychosocial dysfunction both are required to diagnose personality pathology (Livesley et al., 1994; Leising & Zimmermann, 2011). Second, the malleability of personality dysfunction (which tends to vary more over time than personality traits) makes it a promising target for treatment (e.g., Bastiaansen, De Fruyt, Rossi, Schotte, & Hofmans, 2013; Skodol, 2011). Third, dysfunction has been shown to index the severity of personality pathology (e.g., Hopwood et al., 2011; Morey et al., 2013), which, in turn, predicts treatment outcomes more strongly than traits. Fourth, it is likely that dysfunction and traits inform different treatment decisions; namely, dysfunction may indicate the level of care required (e.g., inpatient vs. outpatient), whereas traits may guide selection of a particular therapeutic technique or modality (Bastiaansen et al., 2013).

However, it is unclear whether it is possible to assess PD traits and personality dysfunction distinctly. Indeed, evidence indicates that maladaptive personality trait measures tend to overlap substantially with a range of personality dysfunction measures (e.g., Berghuis, Kamphuis, & Verheul, 2014; Hentschel & Pukrop, 2014; Mullins-Sweatt & Widiger, 2010) and that such findings are consistent with conceptual overlap, rather than measurement redundancy. For instance, Zimmerman and colleagues (2015) performed a joint factor analysis of 60 individual LPFS descriptions and scales of the PID-5 informant version and found a significantly better fit for a model in which trait and dysfunction indicators were allowed to load on the same factors. Although some trait domains emerged relatively purely (Disinhibition, Psychoticism) in the best-fitting model, negative affectivity traits and self-dysfunction loaded together, and antagonistic traits loaded on an interpersonal dysfunction factor (Zimmerman et al., 2015). Finally, Calabrese and Simms (2014), in a ten-day prospective study of PD and related impairments, found that baseline dysfunction ratings failed to predict daily dysfunction above and beyond maladaptive personality traits, calling into question the distinction between PD traits and dysfunction.

In general, research examining the incremental validity of maladaptive traits and dysfunction in predicting personality pathology has found that maladaptive personality traits evidence significant incremental validity relative to dysfunction, whereas the opposite pattern has not held (e.g., Berghuis et al., 2014; Hentschel & Pukrop, 2014). However, it is important to note that the degree to which traits and dysfunction overlap varies across both dysfunction subdomain and PD type. For instance, in one recent study of incremental validity at the PD level of analysis (Bastiaansen et al., 2013), SIPP Identity Integration incrementally predicted borderline PD above PD traits, SIPP Self-Control incrementally predicted antisocial PD and borderline PD, SIPP Relational Functioning incrementally predicted schizoid PD, and SIPP Responsibility incrementally predicted antisocial PD. However, such findings are preliminary, and future work would do well to clarify and confirm the associations between particular types of personality dysfunction and particular PDs.

Development of the LPFS was informed by extant clinician-rated personality dysfunction measures and secondary data analysis (Zimmerman et al., 2015). Therefore, empirical validation is necessary, and results have been mixed. Empirical findings generally have been supportive of the structural validity of the LPFS, with a handful of notable exceptions. First, Zimmerman and colleagues’ (2015) confirmatory factor analyses of LPFS ratings indicated that self-reflective functioning, currently an aspect of Self-Direction, also is significantly associated with interpersonal functioning. They also found that the Interpersonal Functioning domain captures Empathy significantly better than Intimacy, suggesting a three-domain structure (Self Functioning, Prosocial Functioning, Relational Functioning) as a viable alternative (Zimmerman et al., 2015). Second, Bastiaansen and colleagues (2013) suggested that the emotion regulation aspect of Identity, which overlaps extensively with the Criterion B Emotional Lability trait, should be eliminated in service of incremental validity. Finally, little empirical support has been offered to justify the disorder-specific impairment descriptors included in the AMPD. Correlational analyses indicated that disorder-specific impairments were uniformly moderately associated with all trait- and criterion-specified PDs, rather than being uniquely associated with any single PD (Anderson & Sellbom, 2018).

In sum, although some desire a way to conceptualize and measure personality dysfunction separately from PD traits, it remains to be seen whether these two related aspects of personality pathology can be psychometrically disentangled. Further, whether dysfunction evidences incremental validity relative to PD traits in the prediction of personality pathology remains an open question.

The Role of Adaptive Personality Traits

Although this chapter’s focus is on assessing personality pathology, some researchers and therapists have argued that adaptive personality traits and personal strengths are also clinically important (Cheavens, Strunk, Lazarus, & Goldstein, 2012; Costa & McCrae, 1992; Padesky & Mooney, 2012). Indeed, given the complexity of individual differences, it is likely that even individuals with severe personality pathology have some strengths or adaptive traits (e.g., Miller, 1991). Adaptive personality traits may serve protective functions, lead to positive life outcomes, and perhaps facilitate therapeutic interventions (Miller, Pilkonis, & Mulvey, 2006; Ozer & Benet-Martinez, 2006). Furthermore, given the overlap of PD impairment and maladaptive personality traits noted above (e.g., Berghuis et al., 2014; Hentschel & Pukrop, 2014; Mullins-Sweatt & Widiger, 2010), adaptive traits may provide relatively unique information about individuals (Hopwood et al., 2011).

For example, trait conscientiousness – which is part of the Big Five/FFM model – is related to positive life outcomes, such as educational achievement, job performance, and health (Bakker, Demerouti, & ten Brummelhuis, 2012; Bogg & Roberts, 2004; Poropat, 2009). Furthermore, considerable psychotherapy research suggests that it predicts positive treatment outcomes (Anderson & McLean, 1997; Bottlender & Soyka, 2005). Although there is limited research on mechanisms that may explain this association, some work suggests that more conscientious individuals feel more engaged early in treatment (Samuel, Bucher, & Suzuki, 2018), are more likely to complete therapy homework (Miller, 1991), and are more likely to attend sessions (Miller et al., 2006). Many of the assessments in Table 14.1 have scales for assessing maladaptively low conscientiousness; however, only a handful explicitly assess adaptively high conscientiousness (i.e., FFF, FFMSS, SIFFM). That said, some recent research rooted in item response theory suggests that even measures that primarily assess personality pathology (e.g., PID-5) can provide substantial information about adaptively high conscientiousness (e.g., Suzuki, Samuel, Pahlen, & Krueger, 2015).

In contrast to conscientiousness, low agreeableness (e.g., callousness) is generally viewed as maladaptive, whereas high agreeableness is considered adaptive. Research indicates that high agreeableness is related to positive therapy outcomes (Canuto, Meiler-Mititelu, Herrmann, Giannakopoulos, & Weber, 2008; Ogrodniczuk, Piper, Joyce, McCallum, & Rosie, 2003) and that this relation may be explained by more dramatic improvements in therapeutic alliance over time (e.g., Hirsh, Quilty, Bagby, & McMain, 2012). These findings are consistent with research showing that therapeutic alliance is a crucial factor in effective psychotherapy (e.g., Flückiger, Del Re, Wampold, Symonds, & Horvath, 2012) and that agreeableness more generally promotes positive interpersonal relations (Ozer & Benet-Martinez, 2006; Williams & Simms, 2016). Similar to conscientiousness, most measures in Table 14.1 do not explicitly aim to assess adaptive high agreeableness; however, these maladaptivity-focused measures likely still provide considerable information about adaptive agreeableness (Suzuki et al., 2015). Although other adaptive traits have been shown to have clinical relevance (e.g., openness to experience; Miller et al., 2006), the above examples of agreeableness and conscientiousness provide useful illustrations. Further research is needed on the role of adaptive traits in PD assessments and how such information can be integrated into broader PD models.

Maladaptive Unipolarity vs. Bipolarity

The examples in the preceding section on adaptive traits imply that one extreme, or “pole,” of a trait dimension is maladaptive (e.g., low conscientiousness) and the opposing pole is adaptive (e.g., high conscientiousness); however, whether traits are maladaptive at one pole (i.e., maladaptively unipolar) or at both (i.e., maladaptively bipolar) is presently a matter of disagreement (e.g., Samuel & Tay, 2018; Williams & Simms, in press). It is important to resolve this debate, as it has implications for the representation of traits in diagnostic systems (Krueger et al., 2011; Samuel, 2011) and may influence how the measures in Table 14.1 are interpreted (e.g., whether low scores on PID-5 detachment are considered maladaptive). Despite the importance of this topic, it is under-researched and beset by a number of conceptual difficulties.

The “scale polarity” column in Table 14.1 represents what is typically claimed about each measure. Aside from the fact that the polarity of scales is often not discussed, it is often the case that conclusions about polarity are based on whether traits are measured by indicators (e.g., items) that appear to be conceptual opposites (e.g., exhibitionism vs. social withdrawal) that are maladaptive. Although informative, inferences about constructs based on scale characteristics (e.g., item-total correlations) may be limited; a construct validity perspective (Cronbach & Meehl, 1955) would suggest that a better understanding of maladaptive bipolarity could be reached through examining how traits relate to external impairment and psychopathology variables. For instance, meta-analyses of FFM and AMPD relations to common mental disorders (e.g., Hopwood, Thomas, Markon, Wright, & Krueger, 2012; Kotov, Gamez, Schmidt, & Watson, 2010) and PDs (Fowler et al., 2015; Samuel & Widiger, 2008) generally support maladaptive unipolarity, with the exceptions of a moderate (i.e., r = .33) correlation between histrionic PD and extraversion, as well as a small association (i.e., r = .24) between conscientiousness and obsessive-compulsive PD. A similar picture emerges when relations to general impairment (e.g., low well-being) are considered, as FFM and AMPD traits tend to relate to poor functioning at one trait pole (Calabrese & Simms, 2014; Ro & Clark, 2013). Thus, these literatures suggest some evidence of maladaptive bipolarity for conscientiousness and extraversion, although the relation for extraversion to histrionic PD may be complex and primarily accounted for by low agreeableness (Gore, Tomiatti, & Widiger, 2011).

An additional conceptual problem with explorations of trait polarity is the focus on linear relations with psychopathology and impairment. As some researchers have noted (Samuel, 2011; Williams & Simms, in press), if a trait is related to impairment at both poles and is adaptive in the middle of the dimension, then the form of its relation to impairment would be U-shaped (i.e., curvilinear). Thus, correlations and linear regression would need to be supplemented by polynomial regressions or other appropriate analyses. Few studies have examined curvilinear relations between traits and psychopathology or impairment. One of the first explicit studies of such relations (Carter, Guan, Maples, Williamson, & Miller 2016) found a curvilinear relation between conscientiousness and well-being, although the decrement in well-being at high levels of conscientiousness was minor relative to the lack of well-being associated with low conscientiousness. Recently, Williams and Simms (in press), examined curvilinear relations of FFM and AMPD domains with a range of psychopathology and general impairment variables, but found no evidence of maladaptive bipolarity in models focused on these relations. Although there have been mixed findings for maladaptive bipolarity when examining curvilinear relations, recent statistical advances (e.g., ideal point scoring; Carter et al., 2016) and methodological considerations (e.g., more deliberate sampling; Samuel & Tay, 2018) may increase the likelihood of uncovering curvilinear relationships.

As a whole, whether personality traits are maladaptively bipolar has been understudied in the PD literature. More focused research on this topic may improve our understanding of trait models and the measures developed to assess them; however, until then, researchers and clinicians will need to carefully consider the bipolarity of the scales they use. The designations in Table 14.1 provide a starting point for such thinking, but should be supplemented by examining recent research on these measures.

Multisource Assessment

The “Formats” column in Table 14.1 lists methods reflecting varied information sources: the self, an informant (parent, spouse, peer, etc.), and trained assessors (clinicians). Although self-reports are the most frequently used assessment information source and provide valid data on personality pathology (as evidenced by convergent validity with important outcomes; Dawood & Pincus, 2016; Ozer & Benet-Martinez, 2006; Yen et al., 2009), theory and research suggest the limitations of self-report measures as stand-alone assessments of personality pathology (Hopwood & Bornstein, 2014; Carlson, Vazire, & Oltmanns, 2013). In fact, both informant-reports (Oltmanns & Turkheimer, 2009) and interviews (Stepp, Trull, Burr, Wolfenstein, & Vieth, 2005) provide unique and valid information about personality pathology, above and beyond self-report assessments. Researchers and clinicians should carefully consider the value and limitations of individual methods of assessment, as well as how multiple sources of information can be combined.

Beyond recognizing the value of multiple assessment methods, it is useful to consider whether the relative value of a source depends upon the construct being assessed and why this might be, as this allows theoretical and empirical principles to guide multi-method assessment. One set of principles comes from Vazire’s (2010) Self–Other Knowledge Asymmetry model, which proposes that the relative validity of self- and informant-reports is a function of a trait’s (a) observability (e.g., involves overt behavior) and (b) evaluativeness (e.g., is socially desirable). Specifically, when assessing PD-related features, self-reports are likely to provide more valid information on less observable traits (e.g., neuroticism), whereas informants can contribute substantial unique information on evaluative traits that are relatively observable (e.g., agreeableness; Carlson et al., 2013). However, it is important to note that the self–informant relationship also influences the validity of ratings, such that intimate informants (spouses, close family, etc.) can also provide valid information about less observable traits (Connelly & Ones, 2010). Limited research exists on factors that influence the relative value of clinician reports (Galione & Oltmanns, 2014); however, they are likely (a) improved by the use of structured instruments and (b) most useful when self-reports cannot be relied upon due a lack of insight regarding the consistency and impairment associated with a particular PD dimension (e.g., Trull et al., 1998).

Ultimately, multiple sources of information may be useful for assessing PD dimensions; however, the integration of such data can prove complicated when sources disagree. It is beyond the scope of this chapter to fully treat this topic (see Hopwood & Bornstein, 2014); however, it is worth recognizing several considerations relevant to both clinicians and researchers. First, reports from a single source reflect both shared and unique information, as well as error. It follows from this that statistically combining or averaging across sources will remove source-specific error, as well as unique and valid information provided by individual sources (Galione & Oltmanns, 2014). Second, it may be important to consider the reasons for discrepancies across sources, as these discrepancies can provide information about personality pathology as well (Mosterman & Hendriks, 2011). Finally, it is worth noting that not all measures in Table 14.1 have formats for multiple sources. Given this, it is important that clinicians and researchers consider their needs for multi-method data as they choose measures for studies and clinical assessments.

Working Toward a Consensual Set of PD Facets

The measures described above can be understood as residing within a broader higher-order structural model of normal and abnormal personality traits. The FFM represents five higher-order dimensions with roots in the normal-range personality literature. The PSY-5 includes a similar set of maladaptive personality dimensions that are keyed in the direction of their most maladaptive poles. Despite some apparent dissimilarities between these higher-order models (e.g., the FFM includes openness, whereas the PSY-5 includes the domain of psychoticism), a growing literature has shown that measures representing each higher-order model can be represented in the same structural model (e.g., Samuel, Simms, Clark, Livesley, & Widiger, 2010; Wright & Simms, 2014).

Historically, there has been much less consistency across models with respect to their lower-order facets. Widiger and Simonsen (2005, 2006), for example, summarized 18 faceted PD models and organized the facets rationally into a five-factor scheme based on the FFM/PSY-5. Well over 100 facets were organized in this way, suggesting that different measures have proposed many different ways to conceptualize the narrower facets that give rise to the broad domains of PD traits. Several themes were apparent from their collection of facets. First, within each broad domain, there was substantial overlap across similarly named traits (e.g., sociability and social closeness on the one hand and aloofness, detachment, and social avoidance on the other all appeared to tap quite similar aspects of interpersonal behavior in the extraversion-introversion domain). Second, some lower-order facets were listed across multiple domains (e.g., alienation, entitlement, social closeness, dependency), which was likely due to different conceptualizations of these traits across models. Widiger and Simonsen (2006, p. 15) concluded “that an important goal of future research will be the identification of a common ground among alternative dimensional models of personality disorder.”

So, where do we stand, more than a decade later, with respect to Widiger and Simonsen’s (2006) conclusion? As noted earlier in this chapter, several new faceted PD measures have been developed (e.g., PID-5, CAT-PD, and the collection of FFM-PD measures), leading to mixed progress with respect to a consensual lower-order facet structure for personality pathology. On a positive note, the CAT-PD and PID-5 measures, despite arising through relatively independent processes, are quite similar at the facet-level: Of the PID-5’s 25 facets, the CAT-PD has a direct one-to-one match for 24 of them (PID-5 deceptiveness is folded into CAT-PD manipulativeness). However, the CAT-PD also includes several additional facets that are arguably important to the broad assessment of personality pathology (self-harm, norm-violation, etc.) and that have demonstrated incremental validity relative to the PID-5 (Evans & Simms, 2018; Yalch & Hopwood, 2016). Moreover, the FFM-PD measures include many different facets whose connections with the PID-5 and CAT-PD models are less easily described (e.g., Timorousness). Complicating the connections with the FFM-PD facets is that the eight FFM-PD measures often include overlapping facets that have been conceptualized differently to best represent the given PD they were designed to represent.

Thus, although progress has been made with respect to identifying a consensual facet structure for personality pathology, much more work is needed. One recent development may hasten this process: the Hierarchical Taxonomy of Psychopathology (HiTOP; Kotov et al., 2017) consortium – whose mission it is to develop a consensual dimensional psychiatric classification system – is in the process of developing measures to represent the full domain of psychopathology dimensions, including those related to PDs. This process, if successful, should further hone our understanding of the lower-order facets of personality pathology.

Summary, Conclusions, and Future Directions

In this chapter, we have summarized the prominent dimensional measures of traits and impairment related to personality pathology. Much progress has been made in the dimensional assessment of personality traits that are presumed to underlie PD, including significant progress toward a consensual facet structure for PD traits. However, the distinctions made in the literature between PD traits and PD functioning/impairment have resulted in two related sets of measures whose interconnections have only become a recent focus in the literature. An important task for the PD literature is to address whether PD traits and impairment are indeed differentiable aspects of personality pathology, as this question has important implications for the measures reviewed here, as well as the broader conceptualization of personality pathology in our classification systems.

Another task for the PD community to address is that of clinical utility. We have attempted in Table 14.1 and throughout the text to note the features of the reviewed measures that serve the interests of clinical utility. Dimensional PD measures appear to vary considerably in terms of whether they include such features. Measures attached to existing batteries, such as the MMPI-2-RF and PAI, are in the best position to have immediate clinical impact given that these measures already have enjoyed considerable traction in applied practice. Conversely, more modern measures, such as the PID-5 and CAT-PD, may have a longer road to travel to become useful clinical instruments. All too often, researchers focus on developing research measures only and neglect adding the features that might make them more useful in clinical settings. This is true of some of the measures reviewed here, especially the measures of PD functioning/impairment, which largely lack adequate norms or clear interpretive guidelines.

Notably, clinical psychologists and related practitioners are often relatively adherent to the measures they initially elected to use in their clinical practice. For example, numerous reviews have documented that practicing clinicians continue to favor measures such as like the MMPI-2, Rorschach Inkblot Method, and Thematic Apperception Test, despite the information provided in reviews like this and the literature more broadly that more modern measures are available that provide a more nuanced and evidence-based way to assess personality pathology (e.g., Piotrowski, 1999). Why might this be? Although a full treatment of this question is beyond the scope of this chapter, it is clear that current PD researchers will need to do more than they are currently doing to counter this phenomenon. Adding features to tests to improve their clinical utility (e.g., strong norms, validity scales, interpretive materials, scoring services) is an important and necessary first step to improve the state of clinical PD assessment. However, more is probably needed, including efforts to interact directly with clinicians in workshops and continuing education activities, as well as to influence the methods emphasized in training programs for psychologists and allied mental health professionals.

In sum, there is no shortage of ways to assess the features of personality pathology through a dimensional lens. Researchers in this domain would do well to continue working toward integration across models (e.g., HiTOP) and building clinically useful measures of dimensional PD features.

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