Abstract
Clinical accounts suggest grandiosity is an important characteristic of both psychopathy and narcissism. This study examined the relationships between grandiosity and each of these personality disorder syndromes, using a novel index, namely the Grandiosity Index. Seventy-five incarcerated males completed clinical interviews of psychopathy and narcissism and a self-report inventory of narcissism and were rated on interpersonal measures of psychopathy and narcissism. Trained research assistants rated participants on the Grandiosity Index. Analyses provided preliminary evidence of construct validity for the index. Scores on the Grandiosity Index were significantly correlated with scores on both clinical and interpersonal measures of psychopathy and narcissism and with self-reported narcissism. Regressions demonstrated that the Grandiosity Index explained substantial unique variance in psychopathy after controlling for scores on narcissism. This study demonstrates that grandiose features are associated uniquely with clinical ratings of psychopathy, though not significantly more with psychopathy than with narcissism.
Keywords
Introduction
Personality disorders affect a substantial proportion of the population and place costly burdens on society (Coid, 2003). Psychopathy and narcissism are two of the most socially aversive personality disorder syndromes, and both have received increasing research attention in recent years. There is evidence for substantial comorbidity among these personality disorder syndromes, and several characteristics associated with each syndrome have also been reported to correlate with the other (Lee & Ashton, 2005; Paulhus & Williams, 2002). One such characteristic, prominent in clinical descriptions of both psychopathy and narcissism, is grandiosity. Both psychopathic and narcissistic individuals are often described as exhibiting an inflated sense of their abilities, accomplishments, and importance relative to those of others, which makes grandiosity an important clinical construct. However, because few studies have examined grandiosity as a separate or distinct construct, and because no prior studies have examined the relative association of grandiose sense of self with both syndromes in the same sample, this study examined whether scores on a novel measure of grandiosity were differentially related to psychopathy versus narcissism, as well as the extent to which each personality disorder syndrome was uniquely characterized by grandiosity.
Psychopathy is defined by a lack of empathy, guilt, or remorse; shallow affectivity; callous manipulation and exploitation of others; a grandiose sense of self-worth; impulsivity; irresponsibility; and persistent antisocial tendencies (Hare, 1991). It is an important predictor of criminal behavior, including violence and recidivism (Hart & Hare, 1997; Salekin, Rogers, & Sewell, 1996). Psychopathy is comprised of two correlated factors (Harpur, Hare, & Hakstian, 1989), which are further subdivided into four facets (Hare & Neumann, 2006; Neumann, Hare, & Newman, 2007). Factor 1 is comprised of the interpersonal and affective facets, which have been commonly referred to as the core personality features of psychopathy. Interpersonally, psychopathic individuals are deceptive, dominant, and manipulative. On the affective level, such individuals exhibit shallow affectivity and lack empathy, guilt, and remorse. Factor 2 is comprised of the lifestyle and antisocial facets, which reflect traits and behaviors indicative of an unstable and antisocial lifestyle, such as poor anger control, parasitic lifestyle, impulsivity, and irresponsible behavior (Hare, 1991; Harpur et al., 1989). Thus, individuals who are high on the lifestyle and antisocial facets are also more likely to exhibit higher rates of Antisocial Personality Disorder (Antisocial PD; Hare, 1991; Hare, Hart, & Harpur, 1991).
Narcissistic Personality Disorder (NPD) is a pervasive pattern of grandiosity characterized by dominance, exhibitionism, exploitation, feelings of superiority and entitlement, and a grandiose sense of self-importance (American Psychiatric Association [APA], 2013). In addition to people with NPD, there are those who display narcissistic attitudes and behaviors, yet do not meet full diagnostic criteria for NPD; however, individuals in both categories share many similar features. Narcissistic individuals use grandiose and inflated views of themselves while devaluing others (Morf & Rhodewalt, 2001). In addition, people with narcissistic features exhibit extreme vanity; attention and admiration seeking; feelings of superiority, authority, and entitlement; exhibitionism and bragging; and manipulation (Raskin & Terry, 1988).
The relationship between psychopathy and narcissism has received substantial attention. Kernberg (1992) was one of the first to suggest that narcissism, malignant narcissism, Antisocial PD, and psychopathy exist on the same continuum. He argued that psychopathy and narcissism share a pathological self-system, which he termed the “grandiose self-structure”; however, he also posited important differences between psychopathy and narcissism, with psychopathy reflecting more severe disturbances in self and others. As a result, the two syndromes also differ in their interpersonal behavior toward others, with psychopathic individuals maintaining a stable grandiose sense of self through the outward devaluation of others, whereas narcissistic individuals are able to have their needs met from private devaluation of others (Kernberg, 1992).
Regardless of the method of devaluation, it appears these two personalities share many features in common, especially in regard to having a grandiose self-structure at their core (Kernberg, 1992). Both use sly and cunning tactics to obtain desired outcomes (Rauthmann, 2011). In addition, individuals with psychopathic and narcissistic traits engage in outward manipulation of others (Jones & Paulhus, 2010), exhibit callous behaviors and attitudes (Hare, 2003), and demonstrate low levels of agreeableness (Samuel & Widiger, 2008). Hart and Hare (1998) discussed the conceptual overlap between psychopathy and narcissism and concluded that most psychopathic offenders are narcissistic, but not all narcissistic offenders are psychopathic. Murphy and Vess (2003) examined the possibility of personality subtypes of psychopathy based on pure observation of individuals detained at a state hospital. As a result of their observations, they concluded four subtypes underlie psychopathy, which include a narcissistic variant, a borderline variant, a sadistic variant, and an antisocial variant. Individuals who met criteria for the narcissistic variant were said to have characteristics of psychopathy but embody primarily narcissistic features to a pathological degree. Grandiosity, entitlement, and callous disregard for the feelings of others were considered essential features of this subtype (Murphy & Vess, 2003). Given the evidence suggesting psychopathy and narcissism share common features, it is important to examine their similarities and differences in clinical features, as some suggest narcissistic grandiosity negatively impacts psychoptherapy (Ellison, Levy, Cain, Ansell, & Pincus, 2013). In the current study, we examined the extent to which each personality disorder is uniquely associated with grandiosity.
According to the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-5; APA, 2013), grandiosity is defined as, “Believing one is superior to others and deserves special treatment; self-centeredness; feelings of entitlement; condescension toward others.” It has been described as part of one of the core components of both psychopathy (Hare, 1991) and NPD (APA, 2013). Moreover, ratings of grandiosity criteria correlate moderately to highly with clinical ratings of psychopathy and narcissism. The corrected item-total correlation for Item 2 of the Psychopathy Checklist–Revised (PCL-R), “Grandiose Sense of Self-Worth,” is between 0.49 (Hare, 1991) and 0.55 (Medina, Valdés-Sosa, García, Almeyda, & Couso, 2013); likewise, the item-total correlation for Criterion 1 of NPD, “Grandiose Sense of Self-Importance,” is 0.41 (Fossati et al., 2005).
One realm in which grandiosity is evident in these personality disorder syndromes is within the context of interpersonal relationships. Campbell, Brunell, and Finkel (2006) proposed that individuals with narcissistic traits tend to be agentically oriented in that they are more focused on themselves rather than those around them. Lee and Ashton (2005) examined relationships of personality traits associated with the Dark Triad (i.e., Psychopathy, Machiavellianism, and Narcissism) with the variables of the Five-Factor Model of personality and a six-dimensional model of personality, the Honesty-Humility, Emotionality, Extraversion, Agreeableness, Conscientiousness, and Openness to Experience (HEXACO) model, which closely resembles the Big Five personality factors except for the addition of Honesty-Humility. They noted differences between psychopathy and narcissism such that psychopathy showed a moderate negative correlation with Big Five Agreeableness, whereas narcissism did not. Narcissism correlated positively with Big Five Extraversion and HEXACO Extraversion, whereas psychopathy did not. In a subsequent study, Lee et al. (2013) examined the relations of the Dark Triad variables to predict outcome variables related to sex, power, and money. They found that both psychopathy and narcissism scores were correlated most strongly with indices of the Honesty-Humility dimension. These findings again provide evidence that individuals displaying psychopathic and narcissistic traits tend to regard themselves very highly in comparison with others and have difficulty connecting with others.
In summary, grandiosity is a fundamental component of both psychopathy and narcissism, and grandiosity is commonly assessed as part of NPD and psychopathy (e.g., Structured Clinical Interview for DSM Disorders [SCID]; First, Gibbon, Spitzer, Benjamin, & Williams, 1997; PCL-R; Hare, 2003). However, there are no clinical measures that assess grandiosity as a separate construct, only self-report measures. For instance, the Narcissistic Grandiosity Scale (Rosenthal, Hooley, & Steshenko, 2007) asks participants to rate themselves on 16 adjectives, and the Psychological Entitlement Scale (Campbell, Bonacci, Shelton, Exline, & Bushman, 2004) indirectly assesses the extent to which individuals believe they deserve and are entitled to more than others. The Pathological Narcissism Inventory includes a Grandiose Fantasy scale (Pincus et al., 2009), but again, this is a self-report measure.
In addition, to our knowledge, no studies have examined the relationship between grandiosity and psychopathy, as well as grandiosity and narcissism in the same participants. Whereas papers examining the Dark Triad, for example, have investigated similarities and differences between psychopathy, narcissism, and Machiavellianism, we were unable to find any papers that examined strictly grandiosity in psychopathy and narcissism using a clinical measure. Thus, what is not yet understood is whether grandiosity is more central to psychopathy than to narcissism or whether grandiosity is more central to narcissism than to psychopathy. The goal of this study was to examine whether scores on a novel measure of grandiosity were more strongly related to ratings of psychopathy or to ratings of narcissism and whether these relationships were unique after controlling for those with the other personality disorder syndrome.
The current study was designed to objectively examine the utility of a novel measure of grandiosity in an attempt to better understand the constructs of psychopathy and narcissism. First, we preliminarily examined the construct validity of the new measure by examining correlations with two existing indices relevant to grandiosity. Then, we examined how closely related grandiosity was to psychopathy versus narcissism, as well as the extent to which grandiosity was uniquely related to each of the two personality disorder syndromes. Given the fact that grandiosity underlies both psychopathy and narcissism, no prediction was made as to which personality disorder syndrome would be more strongly related to grandiosity. Finally, to examine the extent to which the strength of these relationships depended on the types of measures used, we examined both clinical measures and interpersonal measures of psychopathy and narcissism. As the Grandiosity Index was designed to be a clinical measure, we predicted correlations with the clinical measures of psychopathy and narcissism and the Grandiosity Index would be stronger than correlations between the Grandiosity Index and the interpersonal measures of psychopathy and narcissism. Because self-report data on narcissism were also available, additional analyses addressed relationships between grandiosity scores and scores on self-reported narcissism; however, no self-report data for psychopathy were available.
Method
Participants
Seventy-five incarcerated males at a county jail in the Midwest participated in this study. Men were eligible to participate if they were (a) 18 years or older; (b) not taking psychotropic medications; (c) either charged with or convicted of a felony or misdemeanor; (d) spoke English; and (e) could read at a fourth-grade level (to ensure comprehension of study questionnaires).
Participants ranged in age from 18 to 43 years (M = 26.4, SD = 6.7). The sample was largely African American (63.6%) and Caucasian (23.4%), followed by 10.4% identified as Latino and 2.6% identified as Other. Participants had completed six to 16 years of school (M = 11.4, SD = 1.6), and 48.1% completed high school or obtained a GED.
Measures
Demographics
Individuals provided the following information about themselves: age, ethnicity/race, and level of education.
Psychopathy Checklist-Revised (PCL-R)
The PCL-R (Hare, 1991) is a 20-item clinical measure of the traits and behaviors associated with psychopathy. It has excellent validity and interrater reliability in European American, African American, and Latino American male offenders (Cooke, Kosson, & Michie, 2001; Sullivan, Abramowitz, Lopez, & Kosson, 2006). Each item is rated on a 3-point scale (absent, inconsistent/subthreshold, present) based on information obtained from a semistructured interview, behavioral observations, and collateral file material. The current sample was drawn from a larger sample of 298 inmates. Doctoral-level graduate students trained on the PCL-R administered all interviews. Interrater agreement was excellent for both the full sample and the small number of participants with ratings on both the PCL-R and the International Personality Disorder Examination (IPDE). 1 To avoid direct overlap with a measure related to grandiosity, a modified version of the PCL-R was used. We excluded scores on PCL-R Item 2 and prorated scores to approximate a 20-item score, which was termed the PCL-R Corrected Total Score. Internal consistency for the 19-item PCL-R Corrected Total Score was 0.84.
International Personality Disorder Examination (IPDE)
The IPDE (Loranger, 1988) is a semistructured clinical interview that yields reliable and valid indices of Personality Disorders in the International Statistical Classification of Diseases and Health Related Problems, 10th Revision (ICD-10; World Health Organization [WHO], 1993) and in the text revision of the fourth edition of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV; APA, 1994) classification systems (Blanchard & Brown, 1998). The IPDE addresses all criteria for the 10 Personality Disorders in the Diagnostic and Statistical Manual of Mental Disorders (4th ed., text rev.; DSM-IV-TR; APA, 2000). To establish reliable diagnoses, the behavior or trait must be present for at least 5 years to be considered, and the criterion must be met before the age of 25 years. Independent ratings for the IPDE (based on observed interviews) were available for 22 participants (29.0% of the sample), with intraclass correlation coefficients (ICCs) ranging from .834 (for Paranoid Personality Disorder) to .951 (for Obsessive-Compulsive Personality Disorder). To minimize overlap between the dimensional scores for the Narcissistic Personality Disorder subscale of the IPDE (IPDE NPD Dimensional Scores) and scores on the Grandiosity Index, a Modified IPDE NPD Dimensional Score was created. To reduce predictor-criterion contamination, scores on items 39 and 99 were omitted from the IPDE NPD Dimensional Score when examining correlations with the Grandiosity Index, as they correlated above 0.30 with the Grandiosity Index. Internal consistency for the seven-item Modified IPDE NPD Dimensional Score was 0.73.
The Interpersonal Measure of Psychopathy (IM-P)
The IM-P (Kosson, Steuerwald, Forth, & Kirkhart, 1997) is a 21-item behavioral observational measure of nonverbal behavior and interpersonal processes associated with psychopathy that occur during a semistructured interview. In contrast to the PCL-R, the IM-P is scored solely on the basis of the frequency with which specific behaviors are observed during the interview and subjective impressions of interviewees rather than on an integration of interviewees’ answers to specific questions, collateral file information, and interviewers’ observations of behavior. Thus, IM-P scores are not influenced by information in file reports or by the contents of interviewees’ answers to any given question. Scores on the IM-P have been shown to have a high internal consistency (α = 0.81) and interrater reliability (r = .83) and to correlate approximately twice as highly with scores on Factor 1 of the PCL-R (r = .62) as with scores on Factor 2 of the PCL-R (r = .31). Internal consistency for this study sample 0.93.
The Interpersonal Measure of Narcissism (IM-N)
The IM-N (Bagley & Kosson, 2007) is an unpublished measure designed to assess specific nonverbal behaviors and interpersonal processes associated with narcissism that are observed during a semistructured interview. Like the IM-P, the IM-N is scored based solely on the frequency of specific observed behaviors and subjective impressions of interviewees during an interview. As this has not yet been validated like the IM-P, there are no validity or reliability statistics to report. Internal consistency for this study sample was 0.94.
The Narcissistic Personality Inventory (NPI)
The NPI (Raskin & Terry, 1988) is a 40-item true-false self-report measure of narcissism. Although the NPI is comprised of seven subscales, only NPI total scores were examined in this study. Previous studies indicate good internal consistency for NPI total scores such that the Kuder–Richardson coefficient is 0.83 (Raskin & Terry, 1988) and test–retest reliability is 0.81 (del Rosario & White, 2005). The internal consistency for this sample was good (r = .85).
Grandiosity Index
This new Index was created to assess grandiosity, as described in clinical descriptions and prior research studies that have examined grandiosity (Campbell et al., 2004; Pincus et al., 2009; Rosenthal et al., 2007). The Index was originally comprised of 14 items taken from the PCL-R and the IPDE, as these items were thought to assess grandiose behaviors and attitudes either directly or indirectly; all items were retained in the final analyses, as they demonstrated good face validity. The index was scored based on participants’ answers to specific questions during interviews used to complete PCL-R and IPDE ratings. Some of the items on this scale include intelligence in comparison with other individuals, ease of obtaining a sexual partner, the extent to which one needs to be the center of attention, things that make one really happy, different reasons for leaving a place of employment, and so forth. The items, along with the scoring criteria, can be found in the appendix. Like clinical measures, the Grandiosity Index depended to some extent on raters’ interpretation of participants’ answers. However, the Index did not require any integration of information across answers to different questions or different sources of information. Moreover, because the questions to be used for the Index were determined in advance, it was possible to specify in the scoring key the kinds of answers that would suggest feelings of superiority and entitlement. Consequently, unlike most clinical measures, the Grandiosity Index was designed so raters with little formal training could complete it. If a participant expressed a substantial number of grandiose attitudes and behaviors, he was assigned a score of 2. Answers that did not indicate any features associated with grandiosity were assigned a score of 0. If answers expressed moderate qualities associated with grandiosity, but the evidence was not compelling enough to assign a score of 2, the participant was assigned a score of 1. As the Index is comprised of 14 items, a participant can receive a high score of 28 and a low score of 0. In rare cases where the information in the interviews was not asked directly or an item did not apply to the individual, the item was omitted. In this study, the alpha coefficient for the internal consistency of the Grandiosity Index was 0.66 2 and was based on 61 participants who had scores on all 14 items. Interrater reliability was acceptable (one-way random single rating ICC = 0.74) and was based on 20 participants.
Procedure
Individuals were chosen at random from a sample of eligible male inmates serving a sentence or awaiting trial at a county jail in the Midwest. After learning about the study, inmates who were interested in completing the study provided informed consent in writing. Participants then completed the PCL-R, for which they received $12. After all file information was reviewed and the PCL-R was scored, the interpersonal measures of psychopathy and narcissism were completed based solely on participants’ behavior during the interviewing process. On a separate day, participants were called back to complete the IPDE interview and the NPI; they received an additional $12 for their time. The new measure of grandiosity was completed based on the answers provided in the two interviews.
Results
Scores on the Grandiosity Index correlated significantly with scores on Item 2 of the PCL-R, “Grandiose Sense of Self-Worth” (r = .485, p < .001). In addition, they correlated significantly with scores on the Grandiosity Factor of the IM-P (r = .414, p = .003).
As shown in Table 1, scores on the Grandiosity Index correlated significantly with all measures of psychopathy and narcissism. With respect to the psychopathy measures, the Grandiosity Index correlated moderately with ratings on the PCL-R Corrected Total Score (r = .43, p < .001) and ratings on the IM-P (r = .48, p < .001). With regard to the narcissism measures, the Grandiosity Index correlated moderately with scores on the Modified IPDE NPD Dimensional Score (r = .31, p = .006), ratings on the IM-N (r = .34, p = .006), and scores on the NPI (r = .45, p < .001). Z tests examined whether correlations for the different measures of each personality disorder syndrome differed in magnitude (i.e., clinical vs. behavioral observation vs. self-report). None of the differences between these correlations proved significant, all Zs < 1.20, ps > .20.
Mean, Standard Deviation, and Zero-Order Correlations of Personality Disorder Traits and Psychopathy Facets.
Note. IPDE = International Personality Disorder Examination; NPD = Narcissistic Personality Disorder; IM-N = Interpersonal Measure of Narcissism; NPI = Narcissistic Personality Inventory; PCL-R = Psychopathy Checklist–Revised; IM-P = Interpersonal Measure of Psychopathy.
Both PCL-R and IPDE NPD Dimensional Scores were corrected by removing the influence of scores on items that assessed features related to grandiosity to reduce predictor-criterion contamination. One item was removed from the PCL-R, and two items were removed from the IPDE NPD Dimensional Score. The numbers for some of the study variables varied: IM-N (N = 62), NPI (N = 67), and IM-P (N = 48). Analyses for the other seven variables included 75 participants.
p < .05. **p < .01. ***p < .001.
The two hierarchical regression analyses are presented in Table 2. Each regression examined whether scores on the Grandiosity Index were uniquely related to ratings on a clinical measure of personality pathology after controlling for scores on the other clinical measure of personality pathology. As shown in Table 2, the first regression revealed that grandiosity was related to ratings on PCL-R Corrected Total Scores after controlling for the Modified IPDE NPD Dimensional Scores. The two predictor variables accounted for 25.3% of the variance in PCL-R Corrected Total Scores, F(2, 72) = 12.17, p < .001. Moreover, there were unique relationships between the Grandiosity Index and the PCL-R Corrected Total Score, as well as between the Modified IPDE NPD Dimensional Score and the PCL-R Corrected Total Score, such that 10.8% of the unique variance in PCL-R psychopathy, t(72) = 3.23, p = .002, was explained by the Grandiosity Index when controlling for the Modified IPDE NPD Dimensional Score (see Table 2).
Hierarchical Regression Analyses Examining the Unique Contribution of Grandiosity to Psychopathy and to Narcissism.
Note. After the two predictors were added to Step 2, the overall R2 for Model 1 was .253, and the overall R2 for Model 2 was .172. PCL-R = Psychopathy Checklist–Revised; IPDE = International Personality Disorder Examination; NPD = Narcissistic Personality Disorder.
p < .01.
A parallel hierarchical regression analysis examining whether scores on the Grandiosity Index were related to the Modified IPDE NPD Dimensional Scores after controlling for PCL-R Corrected Total Scores showed that the two predictor variables accounted for 17.2% of the variance in Modified IPDE NPD Dimensional Scores, F(2, 72) = 7.48, p = .001. However, the Grandiosity Index accounted for only 2.7% of the variance in narcissism after controlling for PCL-R psychopathy, t(72) = 1.54, p = .128 (see Table 2).
Discussion
Although it is common practice to consider grandiosity as important to both psychopathy and narcissism, this is the first study that has objectively examined these relationships using a clinically derived measure of the broad construct of grandiosity. Current analyses provide preliminary evidence that grandiosity is relevant to both personality disorder syndromes. This is consistent with prior studies that have suggested there is comorbidity among these personality disorder syndromes, such that several characteristics associated with each syndrome have also been reported to correlate with the other (Lee & Ashton, 2005; Paulhus & Williams, 2002). These analyses also provide evidence for a unique relationship between grandiosity and psychopathy, and they provide evidence for the construct validity of the Grandiosity Index as a broad measure of grandiosity.
Preliminary construct validity analyses indicated that scores on the Grandiosity Index correlated moderately with scores on Item 2 of the PCL-R and scores on the Grandiosity Factor of the IM-P. Notably, scores on the Grandiosity Index correlated moderately with scores on all of the measures of psychopathy and narcissism that were examined. In this context, correlational analyses corroborate clinical descriptions suggesting that grandiosity is related to measures of both psychopathy and narcissism. Moreover, scores on the Grandiosity Index continued to correlate significantly with ratings on the PCL-R Corrected Total Score even after controlling for the Modified IPDE NPD Dimensional Score.
We first consider the zero-order correlations. With regard to psychopathy measures, scores on this Index correlated with ratings on both the PCL-R Corrected Total Score (i.e., an overall psychopathy rating that omitted the score on Item 2, “Grandiose Sense of Self Worth”) and ratings on the IM-P. With regard to narcissism measures, scores on the Grandiosity Index correlated with scores on all three measures: ratings on the Modified IPDE NPD Dimensional Score, ratings on the IM-N, and scores on the NPI.
That scores on the Grandiosity Index correlated with scores on all five measures used to examine psychopathy and narcissism provides evidence that, as expected, grandiosity is an important construct related to both personality disorder syndromes, and it is one that should not be overlooked when examining the characteristic traits associated with psychopathy and narcissism.
With respect to unique relationships, the relationship between grandiosity and psychopathy appears robust and is not solely attributable to narcissism. The Grandiosity Index explained exactly 4 times more unique variance in psychopathy when narcissism was controlled in the regression model than when psychopathy was controlled (Δ R2 = .108 and ΔR2 = .027, respectively). This difference appeared meaningful and suggested grandiosity may be associated more with psychopathy than narcissism; however, the difference between these two partial correlations was not significant.
The study was also designed to examine whether the magnitude of relationships with grandiosity scores was dependent on the kind of measure used. It was predicted that scores on the Grandiosity Index would correlate more highly with ratings on the clinical measures (i.e., the PCL-R Corrected Total Score and the Modified IPDE NPD Dimensional Score) than with ratings on the interpersonal measures or the self-report inventory of narcissism, as the Index was developed as a potential clinical measure. There were no significant differences among the correlations for the different types of measures used to assess psychopathy. Similarly, with regard to narcissism, there were no findings suggesting that grandiosity was more closely related to clinical measures of narcissism than to an interpersonal measure of narcissism. Moreover, there was no advantage of these measures over the self-report measure of narcissism, the NPI.
Because the Grandiosity Index provides a different kind of measure than a self-report measure or a typical interview measure, the current results provide evidence that this kind of measurement approach has utility in assessing grandiosity. As noted earlier, the Grandiosity Index was designed to allow untrained raters to code the level of arrogant, boastful, and grandiose attitudes and behaviors of interviewees from answers provided to interview questions. That raters with relatively little training in the coding of grandiosity were able to achieve good interrater agreement suggests that it is possible to identify answers to interview questions that can be reliably identified as signs of an inflated sense of self-worth. Moreover, that these ratings correlate moderately with other indices of grandiosity, as well as with indices of psychopathy and narcissism, provides evidence that these ratings comprise a valid index of grandiosity. Although the current study only addressed grandiosity, such findings provide preliminary evidence that this method of evaluating a broad psychological construct may have utility in both research and clinical settings in which a researcher or clinician has collected general data about an individual but is interested in a specific clinical or psychological construct for which no validated measure exists.
A limitation of this study is that it is comprised of an all-male sample, so it is unclear how results will generalize to a female sample. Future studies should examine the relationship between grandiosity and psychopathy and narcissism in a female offender sample.
A second limitation of the study is the relatively low internal consistency of the Grandiosity Index. Although the alpha coefficient of 0.66 indicates fair internal consistency, this modest internal consistency raises the possibility that the underlying internal structure of grandiosity may be multifactorial. Future research should examine the factor structure of the Grandiosity Index to determine whether there are different aspects of grandiosity being measured by the Index, as different components of grandiosity may be selectively related to narcissism versus psychopathy. In addition, the alpha coefficient may have improved had the items in the Index been examined with regard to a particular cutoff score used to determine whether the score on each item correlated highly with scores on the rest of the items. Future analyses should consider whether the Index should be modified to maximize internal consistency.
An additional limitation of this study is that a majority of the items that comprise the Grandiosity Index were taken from the PCL-R (i.e., 10 of the 14 items). As a result, it is possible that this imbalance contributed to the larger correlation between the PCL-R Corrected Total Score and the score on the Grandiosity Index. Future analyses should examine whether this had any impact on the correlations that emerged in the study. It should be noted that despite this discrepancy, the correlation between the PCL-R Corrected Total Score and the Grandiosity Index was not significantly larger than the correlation between the Modified IPDE NPD Dimensional Score and the score on the Grandiosity Index.
Relationships between the Grandiosity Index and scores on a self-report measure of psychopathy were not examined. In light of the unique relationships between grandiosity and psychopathy, it would be interesting to examine whether such relationships would also generalize to a self-report measure of psychopathy.
Grandiosity is measured, to an extent, in some clinical measures of psychopathy and narcissism (i.e., the PCL-R and the NPD subscale of the IPDE). Results examining the association between the Grandiosity Index and study variables are consistent with this clinical approach to assessing psychopathy and narcissism. This study demonstrates that grandiose features are associated uniquely with clinical ratings of both psychopathy, though not significantly more with psychopathy than with narcissism. As more studies are conducted that examine the role of grandiosity in these two personality disorder syndromes, the importance of grandiosity in psychopathy and narcissism will become more evident.
Footnotes
Appendix
Acknowledgements
We gratefully acknowledge the assistance of Rick Riddle, G. Mark McCorley, and the staff of the Lake County Jail for their support of this study, and Amy Bagley, Chelsea Brieman, Michael Brook, Allison Brown, Erica Christian, Sarah Hampton, Jami Mach, Christine Meltzer, Katie Montry, Stephanie Smith, Elizabeth Sullivan, Marc Swogger, and Zach Walsh who assisted with data collection and data entry.
Declaration of Conflicting Interests
The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.
Funding
The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This research was funded by National Institute of Mental Health Grant, MH57714, awarded to David S. Kosson.
