Variants of Callous-Unemotional Conduct Problems in a Community Sample of Adolescents Kostas A. Fanti, Chara A. Demetriou & Eva R. Kimonis Journal of Youth and Adolescence A Multidisciplinary Research Publication ISSN 0047-2891 Volume 42 Number 7 J Youth Adolescence (2013) 42:964-979 DOI 10.1007/s10964-013-9958-9 1 23 Your article is protected by copyright and all rights are held exclusively by Springer Science +Business Media New York. This e-offprint is for personal use only and shall not be selfarchived in electronic repositories. If you wish to self-archive your article, please use the accepted manuscript version for posting on your own website. You may further deposit the accepted manuscript version in any repository, provided it is only made publicly available 12 months after official publication or later and provided acknowledgement is given to the original source of publication and a link is inserted to the published article on Springer's website. The link must be accompanied by the following text: "The final publication is available at link.springer.com”. 1 23 Author's personal copy J Youth Adolescence (2013) 42:964–979 DOI 10.1007/s10964-013-9958-9 EMPIRICAL RESEARCH Variants of Callous-Unemotional Conduct Problems in a Community Sample of Adolescents Kostas A. Fanti • Chara A. Demetriou Eva R. Kimonis • Received: 25 February 2013 / Accepted: 26 April 2013 / Published online: 5 May 2013 Ó Springer Science+Business Media New York 2013 Abstract Callous-unemotional traits are believed to be a childhood precursor to psychopathy, and among youth with conduct problems they designate those showing a particularly severe, stable, and aggressive pattern of antisocial behavior. Youth with callous-unemotional traits are a heterogeneous population and, analogous to adults with psychopathy, research suggests that lower anxious primary and high-anxious secondary variants exist. Using a community sample of 2,306 Greek-Cypriot adolescents (M age = 16 years; 49.7 % female), the first aim of the study was to examine whether variants of callous-unemotional traits could be identified using latent profile analysis of scores on measures of callous-unemotional traits, conduct problems, and anxiety. Additional aims of the study were to compare the identified clusters on external measures theorized to distinguish them (i.e., self-esteem, narcissism, impulsivity, sensation seeking and proactive/reactive aggression) and social factors relevant to adolescent development. Results indicated that, in addition to low risk (i.e., low scores on callous-unemotional traits, conduct problems, and anxiety) and anxious (i.e., high scores on anxiety, low scores on K. A. Fanti (&) Department of Psychology, University of Cyprus, P.O. Box 20537, CY 1678 Nicosia, Cyprus e-mail: [email protected] C. A. Demetriou University College London, London, UK e-mail: [email protected] E. R. Kimonis School of Psychology, The University of New South Wales, Kensington, NSW 2052, Australia e-mail: [email protected] 123 callous-unemotional traits and conduct problems) subgroups, two groups of youth scoring high on callousunemotional traits and conduct problems were identified. High-anxious secondary callous-unemotional variants were distinguished by lower self-esteem in combination with greater narcissism, aggression, and markedly higher conduct problems, whereas lower anxious primary variants showed higher self-esteem. Secondary callous-unemotional variants also reported greater susceptibility to peer pressure and popularity striving than primary variants. Both variants exhibited poorer outcomes relative to low risk and anxious youth, although anxious youth reported lower self-esteem and higher impulsivity and reactive aggression scores in comparison with low risk youth. Findings integrate two lines of inquiry focused on subtyping children and adults with psychopathic traits and antisocial behaviors. They also support the utility of subtyping callous-unemotional traits based on conduct problems and anxiety levels and provide information on common and distinct risk factors associated with primary and secondary callous-unemotional variants in a community sample of adolescent boys and girls. Keywords Callous-unemotional traits Conduct problems Anxiety Primary and secondary psychopathy Variants Subtypes Introduction The presence of callous-unemotional traits (i.e., lack of remorse/empathy, callous use of others, shallow/deficient affect) designates an important subgroup of children and adolescents with conduct problems who show a more severe and aggressive pattern of antisocial behavior than youths without callous-unemotional traits (Frick and Author's personal copy J Youth Adolescence (2013) 42:964–979 Dickens 2006; Frick and White 2008). Callous-unemotional traits are believed to be a developmental precursor to adult psychopathy (Frick 1995, 2006; Lynam 1996), capturing the affective dimension that Cleckley (1976) viewed as the hallmark of psychopathy that often is termed the ‘‘affective discomfort’’ component (Hare and Neumann 2010). However, prior research on this potential childhood antecedent points to the combination of co-occurring callous-unemotional traits and conduct problems as a likely precursor to psychopathy as opposed to callous-unemotional traits alone. For example, youth with co-occurring callous-unemotional traits and conduct problems show a distinct temperamental style characterized by fearlessness, reward dominance, and emotional insensitivity to cues of distress and fear in others, similar to deficits observed among adults with psychopathy (Frick et al. 2003b; Blair et al. 2001). Some have challenged the notion that antisocial behaviors be included in conceptualizations of adult psychopathy, suggesting that these behaviors develop downstream of the core personality features (Skeem and Cooke 2010; cf. Hare and Neumann 2010). Even when focused strictly on personality characteristics of psychopathy, traditional theoretical perspectives view these individuals as a largely homogeneous group, as evidenced by many of the diagnostic measures used to classify them (Andershed et al. 2002; Hare 2003; Forth et al. 2003; Lynam 1997). However, conceptualizing psychopathy as a unitary construct has been challenged by evidence of measurable heterogeneity among individuals classified as ‘‘psychopaths’’ (see Skeem et al. 2003). What is not clear is to what extent this heterogeneity maps on to the important distinction between conduct problems with and without callous-unemotional traits that is well established in the juvenile literature. There is growing empirical support for heterogeneity among incarcerated adolescent boys and adult offenders scoring high on measures of psychopathy or callousunemotional traits; the extent of this heterogeneity within community youth, and across gender, has not yet been investigated. These paradigms are rooted in early theory (Karpman 1941, 1948a, b), which introduced the concept of secondary psychopathy acquired through environmental insult, particularly competitive disadvantage (Mealey 1995), parental abuse, rejection, or overindulgence (Karpman 1948a, 1955), and other traumatic experiences (Porter 1996). Karpman (1948a, b) theorized that exposure to early abusive experiences resulted in an excess of negative emotions and unresolved emotional conflict—chiefly hostility—in the child that disturbed the functioning of an otherwise intact conscience, giving the appearance of a ‘‘psychopathic fac¸ade’’ (Karpman 1948b, p. 523). Primary psychopathy, in contrast, theoretically results from a ‘‘constitutional’’ deficit that is manifested in part by a lack 965 of conscience (Karpman 1948a). Hicks et al. (2004) extended this perspective to suggest that personality and temperamental deficits common to primary variants affect their levels of empathic concern, making them less capable of feeling guilt and characterizing them by a generalized lack of concern for others. Contemporary research on psychopathy variants predominately distinguishes them on the basis of anxiety, given its centrality to distinguishing variants in Karpman’s (1941) taxonomy (e.g., Falkenbach et al. 2008; Kosson and Newman 1995; Skeem et al. 2007). This contradicts Cleckley’s (1941) view of psychopathy as a personality disorder characterized by a lack of anxiety, leading some to label his conceptualization as that of primary psychopathy. With empirical evidence for this anxiety-based distinction, Hicks et al. (2004) labeled primary variants in their study as ‘‘emotionally stable’’ given their fearlessness, absent reaction to stress and high social dominance, and secondary variants as ‘‘aggressive psychopaths’’ characterized by high negative emotionality. Several theorists posited that secondary psychopaths may be more aggressive and violent than primary psychopaths (Blackburn 1987; Karpman 1948a, 1955; Lykken 1995; Mealey 1995). Similarly, Hicks et al. (2004) found that high-anxious secondary male variants had more extensive histories of violence and criminality and displayed greater aggression, reactive hostility, and impulsivity than primary variants. Research conducted with juvenile offenders not only confirms that psychopathy variants can be identified among male samples and are distinguishable by varying anxiety levels, but that they also show different rates of violence. For example, within a subsample (n = 116) of male juvenile offenders in the United States scoring high on the Youth Version of the Psychopathy Checklist (PCL:YV), high-anxious secondary variants showed more institutional violence compared with lower anxious primary variants (Kimonis et al. 2011). Specifically, 92 % of secondary variants compared with 69.4 % of primary variants engaged in institutional violence across a two-year incarceration period. With regard to the quality of their violence, secondary variants engaged in more reactively aggressive incidents (82 %) than primary variants (54 %), although they did not differ significantly in their rates of proactive (i.e., instrumental) violence. Similarly, among a sample of incarcerated American youth with high scores on a self-report measure of psychopathy (N = 132), Vaughn et al. (2009) found that secondary variants manifested more total self-reported delinquency than primary variants. It would be reasonable to conclude from these studies that conduct problems, of which delinquent acts and aggression towards people or animals are types, might distinguish primary and secondary variants. However, Karpman (1941) described psychopathy variants as being phenotypically indistinguishable, which 123 Author's personal copy 966 would suggest that levels of conduct problems would not differ significantly between them. Prior studies with juvenile samples are not well-positioned to address this question since they focused on offender samples who tend to have high rates of conduct problems (e.g., Vaughn et al. 2009; Kimonis et al. 2012b). Impulsivity and narcissism are two other dimensions of juvenile psychopathy that might distinguish variants. For example, Kimonis et al. (2011) found that impulsivity and narcissism differed between juvenile psychopathy variants, whereas callous-unemotional traits did not. Regarding impulsivity, Kimonis et al. (2012a) reported that highanxious secondary psychopathy variants scored significantly higher on impulsivity compared with lower anxious primary variants. With regard to narcissism, Skeem et al. (2003) hypothesized that secondary psychopathy may be associated specifically with covert narcissism—relating to feelings of inferiority and worthlessness, anxiety, and vulnerability—whereas primary psychopathy may be associated with overt narcissism (i.e., grandiosity, exhibitionism, invulnerability, and entitlement; Wink 1996). On this basis, low self-esteem in combination with high narcissism might differentiate secondary from primary psychopathy variants. Although not examined directly, Vaughn et al. (2009) found that secondary juvenile psychopathy variants scored higher on a related construct—the interpersonal sensitivity scale of the Brief Symptom Inventory—compared with primary variants. This scale measures feelings of inferiority, self-consciousness, and dislike by others, which are all indicators of low selfesteem. Based on evidence that the combination of a low or a fragile self-concept with a grandiose self-view contributes to the severity of aggressive behavior (Barry et al. 2003; Baumeister et al. 1996), and the greater levels of aggressive and violent behavior among secondary psychopathy variants (Hicks et al. 2004), it is hypothesized that the high narcissism/low self-esteem combination will be more evident among youth in the secondary than the primary variant subgroup. Sensation seeking is another personality difference investigated between psychopathy variants to distinguish them. Lykken (1995) proposed that secondary psychopathy is characterized by high sensation seeking compared with primary psychopathy. However, this distinction has received relatively weak and inconsistent support in prior studies of adults (Falkenbach et al. 2008; Newman et al. 2005; Poythress et al. 2010), and it is unclear to what extent any differences will be identified within youth samples. Comparing primary and secondary callous-unemotional variants on various personality traits, such as impulsivity, narcissism/self-esteem, and sensation seeking, is expected to provide important evidence for differentiating these groups. 123 J Youth Adolescence (2013) 42:964–979 To date, the majority of research on juvenile psychopathy/callous-unemotional variants has been limited to male offender populations, constituting a critical gap in research and fertile grounds for extending research to community youth and to girls. Normative factors relevant to the adolescent developmental period may be more important to shaping the development of antisocial and aggressive behaviors among youth in typical school settings than they are in atypical residential correctional settings. Peer processes might be particularly important to the aims of the current study since variables associated with primary and secondary psychopathy, including conduct problems, callous-unemotional traits, and anxiety, have been shown to be related to impaired peer relationships (see for example, Loeber et al. 2000; Verduin and Kendall 2008; Waschbusch and Willoughby 2008). Specifically, popularity, and the need to achieve it within one’s peer group, has been widely examined as a contributor to youths’ antisocial behavior. Empirical evidence also suggests heterogeneity among popular children and adolescents with the existence of popular prosocial and popular antisocial subtypes (Luthar and McMahon 1996; Parkhurst and Hopmeyer 1998; Rodkin et al. 2000). Notably, based on teacher, peer, and self-perceptions, youth in the popular antisocial subtype have been characterized as extremely aggressive and disruptive with co-occurring internalizing problems (Rodkin et al. 2000), indicating a possible association between secondary psychopathy and popularity status. Further, Adler and Adler (1998) noted that both unpopular and popular youths who value and pursue popularity are more prone to engage in delinquent and aggressive behaviors in an attempt to impress others and improve their social status or to maintain their already popular and dominant status, respectively. Moreover, these adolescents tend to experience higher anxiety levels and are especially reactive to social exclusion (Adler and Adler 1998), which makes them particularly susceptible to peer influence and pressure (Cohen and Prinstein 2006; see also Allen et al. 2005). Oftentimes, these attitudes go hand in hand with adolescent rebellion against authority (i.e., nonconformity) in an effort to seek peer approval (Burnett et al. 2011). Although not directly relevant, prior research on juvenile psychopathy variants reporting greater psychosocial immaturity among high-anxious secondary variants compared with primary variants (Kimonis et al. 2011) suggests that secondary psychopathy variants also may be more susceptible to negative peer influences. To the contrary, Kerr et al. (2011) found that adolescents high on callous-unemotional traits were less likely to be influenced by their peers’ delinquent behavior, suggesting that youth with callous-unemotional traits might be less susceptible to peer pressure; however, no prior work has investigated whether callous-unemotional variants differ in their Author's personal copy J Youth Adolescence (2013) 42:964–979 susceptibility to peer pressure. Taking into account these adolescent peer processes is of great importance since the association of popularity striving, susceptibility to peer pressure, and conformity with psychopathic traits has yet to be explored. Present Study Parallel approaches to making sense of heterogeneity in childhood conduct problems and in adult psychopathy have not previously converged despite strong evidence supporting the relevance of co-occurring callous-unemotional traits and conduct problems to psychopathic personality disorder. Putting aside controversies over whether antisocial behaviors captured by measures of childhood conduct problems should be considered core to psychopathy, this study aimed to examine to what extent the combination of callous-unemotional traits and conduct problems, which has been linked to emotional deficits similar to adult psychopathy, maps on to conceptualizations of primary and secondary psychopathy that distinguish more homogeneous subgroups on the basis of anxiety levels. Prior research suggests that adolescent offenders—many of whom show high rates of conduct disorder diagnosis—with callousunemotional/psychopathic traits are a heterogeneous population that can be disaggregated on the basis of anxiety scores. By studying a large sample of community youth who show greater variability in their levels of conduct problems, we are able to address yet unanswered questions such as: Are primary and secondary distinctions of psychopathy relevant to youth with callous-unemotional traits with and without co-occurring conduct problems? Are youth with co-occurring conduct problems and callousunemotional traits heterogeneous with respect to their variant status? Thus, the primary aim of the current study was to examine whether variants of callous-unemotional traits could be identified among a community sample of adolescent boys and girls on the basis of callous-unemotional traits, conduct problems, and anxiety scores. We hypothesized that we would identify two groups of youth with cooccurring callous-unemotional traits and conduct problems, one with lower anxiety scores consistent with primary psychopathy and one with high anxiety scores consistent with secondary psychopathy, as well as a low risk group. Latent profile analysis was employed to identify the hypothesized groups of children. Latent profile analysis is similar to cluster analysis in that the identified class solutions depend entirely on measured variables; however, it is a more advanced maximum likelihood based statistical model and possesses a number of advantages compared to cluster analysis, such as the reliance on person based 967 probabilities to form classes, the non-reliance on the assumptions of normality and linearity, and the use of more rigorous criteria to decide on final model selection (Pastor et al. 2007). Our second aim was to compare the resulting clusters on several personality and behavioral measures that are theorized to distinguish them, but have received little attention in prior studies of youth and inconsistent findings among adults (i.e., self-esteem/narcissism, impulsivity, proactive/ reactive aggression, and sensation seeking). On the basis of prior research and theory, we hypothesized that secondary callous-unemotional variants would score lower on selfesteem and higher on narcissism, impulsivity, sensation seeking and reactive aggression than primary variants, and that both groups would show poorer outcomes than low callous-unemotional youth. Our third aim was to compare these adolescent community-based callous-unemotional variants on peer factors relevant to adolescent development not previously investigated in the literature, namely susceptibility to peer pressure, popularity striving, and general conformity/obedience. Focusing on these peer processes as they relate to primary and secondary psychopathy in adolescence may be particularly important given that adolescents are more prone to peer influences due to their increased need for individuation from their parents (Steinberg and Monahan 2007). The need for autonomy from parents leads adolescents to be highly dependent on their peers and highly susceptible to their pressures, resulting in antisocial behavior (Erickson et al. 2000). We hypothesized that secondary callous-unemotional variants would report greater susceptibility to peer influences and popularity striving than primary variants, but would not differ on conformity/obedience such that both variants would report lower levels than low risk youth given their higher levels of conduct problems. Finally, taking gender differences into account might also be important because boys tend to score higher on psychopathic traits, are more likely to engage in antisocial behaviors, and tend to score lower on internalizing problems compared to girls (e.g., Fanti and Henrich 2010; Lewinsohn et al. 1998; Marsee et al. 2005). This suggests possible differences in the percentage of boys and girls that might be identified in the primary and secondary variant subgroups. Although research on psychopathy in females is scant relative to males, both primary and secondary psychopathy variants have been identified in male and female adult offender samples (Skeem et al. 2007; Hicks et al. 2004, 2010). For the most part, phenotypic manifestations are similar across gender in that both men and women with secondary psychopathy were distinguished from primary psychopaths by greater anxiety, antisocial and violent behavior; however, adult female offenders reported lower 123 Author's personal copy 968 mean levels of aggression and greater psychopathology (Hicks et al. 2010). To replicate and extend these findings to a community sample of adolescent boys and girls, prevalence differences and phenotypic manifestations of primary and secondary callous-unemotional variants across gender were explored. Method Participants The sample consisted of 2,306 high school students living in Cyprus, and was divided evenly between boys (n = 1,160) and girls (n = 1,146). Adolescents ranged in age between 15 and 18 years at the initial assessment (M age = 16, SD = .89) and data were collected from high school students in grades 10 (39 % of the sample), 11 (31.5 %), and 12 (29.5 %). The sample was diverse in terms of parental education levels; 17.61 % did not complete high school, 47.89 % had a high school education, and 34.5 % had a higher education degree, which is representative of the population in Cyprus. Procedure Following approval of the study by the Cyprus Ministry of Education and Culture, 12 high schools in three different Greek-Cypriot provinces (Nicosia, Larnaca, Limassol) were selected randomly for participation. Parents/guardians were informed of the longitudinal nature of the study and 96 % of those contacted consented to their child’s participation in the study. Ninety five percent of students assented to participate (n = 2,414). In the first year of the study, students completed a battery of questionnaires, which took approximately one hour and included measures used in the latent profile analysis (i.e., callous-unemotional traits, conduct problems, anxiety), and self-esteem, narcissism, and impulsivity. Six months later, youth completed a second assessment of the same duration, which included questionnaires about aggression, sensation seeking, social influences and conformity. A high percentage of students in the original sample (95.51 %, n = 2,306) participated in the follow-up assessment. Attrition was due to an inability to contact students who had moved away from the area or had transferred to a different school. Measures Clustering Measures Callous-Unemotional Traits The Inventory of CallousUnemotional Traits (ICU; Frick 2004) is a 24-item scale 123 J Youth Adolescence (2013) 42:964–979 designed to assess self-reported callous-unemotional traits in youth. The ICU comprises 12 positively worded (e.g., ‘‘I express my feelings openly’’) and 12 negatively worded items (e.g., ‘‘What I think is ‘‘right’’ and ‘‘wrong’’ is different from what other people think’’) that are rated on a 4-point Likert-scale ranging from 0 (not at all true) to 3 (definitely true). Item scores are summed to form a total score that demonstrated adequate internal consistency in the present study, a = .80. Previous research has provided evidence for the validity of ICU scores in community and high risk samples of American, German, and Greek Cypriot youth (Essau et al. 2006; Fanti et al. 2009; Kimonis et al. 2008). Conduct Problems and Anxiety The Checkmate plus Youth’s Inventory-4 (YI-4; Gadow and Sprafkin 1999) is a self-report checklist of DSM-IV symptomatology for the most common disorders of childhood and adolescence. Youth rate YI-4 symptoms on a 4-point Likert scale ranging from 0 (never) to 3 (very often), with middle ratings of 1 (sometimes) and 2 (often). For the purposes of the present study, only items corresponding to the 15-item Conduct Disorder (e.g., ‘‘I stay out at night when I am not supposed to’’; a = .90) and 6-item Anxiety symptoms (e.g., ‘‘I have trouble getting myself to stop worrying’’; a = .85) scales were used. The items were summed to create overall conduct problems and anxiety subscales. Previous research has provided evidence for the validity of the YI-4 in a community sample of Greek Cypriot children (Fanti 2011). In addition, prior work suggests high convergent and discriminant validity in community and clinical samples in the United States (Gadow and Sprafkin 1999; Gadow et al. 2002). External Measures Self-Esteem The Rosenberg Self-Esteem Scale (RSES; Rosenberg 1965) is a 10-item measure of global selfesteem. Individuals report on their current feelings on a five-point Likert scale ranging from 0 (strongly disagree) to 3 (strongly agree). Five items are worded positively (e.g., ‘‘On the whole, I am satisfied with myself’’) and five are worded negatively (e.g., ‘‘At times, I think I am no good at all’’). RSES items are summed to form a total score with higher scores indicating higher self-esteem (a = .73). RSES scores have been found to be associated with ratings of aggression and delinquency (Barry et al. 2009; Bushman and Baumeister 1998). Impulsivity and Narcissism The Antisocial Process Screening Device—Youth Version (APSD; Frick and Hare 2001) is a self-report rating scale designed to assess dimensions of psychopathy among youth. APSD items are Author's personal copy J Youth Adolescence (2013) 42:964–979 rated on a three-point Likert scale ranging from 0 (not at all true) to 2 (definitely true). For the present study, only the 5 items corresponding to the Impulsivity (e.g., ‘‘I do not plan ahead or leave things until the last moment’’; a = .69) and the 7 items corresponding to the Narcissism (e.g., ‘‘I act charming or nice to get things I want’’; a = .73) subscales were used in analyses. There is substantial support for the validity of the self-report version of the APSD and for its ability to designate a group of antisocial youth with deficits in emotional functioning (e.g., Kimonis et al. 2006). Furthermore, self-reported APSD scores were associated with parent ratings of psychopathic traits, aggression, conduct problems and delinquency (Mun˜oz and Frick 2007). Sensation Seeking The Sensation Seeking Scale FormV (SSS-V; Zuckerman, Eysenck, and Eysenck 1978) is a 40-item forced choice questionnaire that was developed to measure individual differences in stimulation and arousal needs. The SSS-V yields four 10-item subscales and a total score. The Thrill and Adventure Seeking subscale assesses the desire to engage in sports or activities involving some physical risk (e.g., ‘‘I often wish I could be a mountain climber’’; a = .79); the Experience Seeking scale assesses the desire to seek out novel experiences through the mind and the senses (e.g., ‘‘I like some of the earthly body smells’’; a = .73); the Disinhibition scale assesses the need to disinhibit behavior in the social sphere (e.g., ‘‘I like wild uninhibited parties’’; a = .78); and the Boredom Susceptibility scale assesses an aversion for repetitive experiences and restless reactions (e.g., ‘‘I can’t stand watching a movie that I’ve seen before’’; a = .75). Scores are summed to form a total score (a = .80) and four subscale scores. The reliability, construct and cross-cultural validity for this instrument is well established (for a review, see Zuckerman 1994). Proactive and Reactive Aggression The self-rating scale of the Proactive and Reactive Aggression Questionnaire (Raine et al. 2006) is a 23-item questionnaire that measures proactive (12 items; e.g., ‘‘Had fights with others to show who was on top’’; a = .90) and reactive aggression (11 items; e.g., ‘‘Gotten angry when others threatened you’’; a = .89). Items are rated on a 3-point Likert scale ranging from 0 (never) to 2 (often) for frequency of occurrence. The items refer either to physical or verbal aggression for both proactive and reactive aggression subscales. Prior research found that proactive aggression scores were associated with delinquency, psychosocial adversity, psychopathic personality, blunted affect, and serious violent offending in a sample of adolescents, while reactive aggression scores were associated with adolescents’ impulsivity, hostility, social anxiety, lack of close friends, 969 unusual perceptual experiences, and ideas of reference (Raine et al. 2006). Social Influences and Conformity The Peer Pressure Questionnaire (PPQ; Santor et al. 2000) is a 30-item selfreport questionnaire that yields three subscales: The 7-item General Conformity subscale assesses the extent to which individuals are obedient and conform to authority in general (e.g., ‘‘I usually do what I am told’’; a = .67); the 11-item Peer Pressure subscale assesses the subjective experience of feeling pressured, urged, or dared by peers to do certain things (e.g., ‘‘My friends could push me into doing just about anything’’; a = .77); and the 12-item Popularity Striving subscale measures an individual’s intention to do certain things in order to be viewed as popular among their peers (e.g., ‘‘I have done things to make me more popular, even when it meant doing something I would not usually do’’; a = .85). PPQ items, which are rated on a 5-point Likert scale ranging from 0 (strongly disagree) to 4 (strongly agree), were averaged to create the three subscales. PPQ subscales were found to predict adolescent well-being (e.g., self-esteem and dysphoria), risk behaviors (e.g., substance use, delinquency, and sexual behavior), and school performance (Santor et al. 2000). Plan of Analysis To address the first aim of identifying primary and secondary callous-unemotional variants, latent profile analysis was conducted with the three continuous indicators of callous-unemotional traits, conduct problems, and anxiety measured at Time 1. Analyses were run using Mplus 6.1 statistical software (Muthe´n and Muthe´n 2010). Latent profile analysis is an extension of latent class analysis that accommodates continuous indicators and identifies heterogeneous latent classes by decomposing the covariance matrix to highlight relationships among individuals, and clusters individuals into latent classes (Bauer and Curran 2004). Separate latent profile analysis models are specified that differ in the number of classes, which allows for the identification of the optimal number of groups to retain. Several statistical criteria are used to compare the relative fit of the various models, including the Bayesian information criterion (BIC), the Akaike information criterion (AIC), the Lo-Mendel-Rubin (LMR) statistic, and the entropy value (Nylund et al. 2007). Models with lower BIC and AIC values are preferred. The LMR statistic tests k – 1 classes against k classes, and a significant Chi square value (p \ .05) indicates that the k – 1 class model is rejected in favor of the k class model (Lo, Mendell and Rubin 2001). A non-significant Chi square value (p [ .05) suggests that a model with one fewer class is preferred. Entropy values greater than .70 are preferable as they indicate clear 123 Author's personal copy 970 classification and greater power to predict class membership (Muthe´n 2000). Latent profile analysis estimation in Mplus outputs two sets of results: (1) scores for each cluster on the measured variables, and (2) the posterior probability of class membership for each case. The average posterior probabilities are taken into consideration in concert with entropy values to determine the precision of classification and the degree to which classes are distinguishable. Average posterior probabilities equal to or greater than .70 imply satisfactory fit (Nagin 2005). To address our second aim of validating identified clusters, we used multivariate analyses of variance (MANOVA) to test for main effects of gender, identified groups, and gender by group interactions (2 9 4 design) on external measures of self-esteem, narcissism, impulsivity, sensation seeking and proactive/reactive aggression. Separate MANOVAs were conducted for conceptually similar and more highly correlated measures. MANOVA also was used to address our third aim of comparing callous-unemotional variants on peer factors, including general conformity, susceptibility to peer pressure, and popularity striving. Because the focus of the study is on primary and secondary callous-unemotional variants, only main effects and interactions involving group were examined in detail, although main effects of gender are reported when significant. Results Descriptive Statistics Means and standard deviations (SD) for the main study variables are reported in Table 1. The average scores for callous-unemotional traits reported in the current study were lower compared to scores of incarcerated youth in the United States (Kimonis et al. 2013), but similar to average scores reported by German community youth (Essau et al. 2006). Correlations among the measured variables also are reported in Table 1. With the exception of self-esteem and conformity, the majority of variables were associated positively with callous-unemotional traits and conduct problems. Anxiety was associated positively with impulsivity, narcissism, reactive aggression, susceptibility to peer pressure, and popularity striving, and associated negatively with self-esteem. Conduct problems were associated positively with both callous-unemotional traits and anxiety, although callous-unemotional traits were not associated significantly with anxiety. Latent Profile Analysis To identify the optimal number of groups to retain, five separate latent profile analysis models were estimated to 123 J Youth Adolescence (2013) 42:964–979 compare the relative fit of models specifying one to five groups. As shown in Table 2, the BIC statistic increased from four classes to five classes and the LMR statistic fell out of significance for the five-class model, suggesting that the four-class model better fit the data. Moreover, the fiveclass model identified a small group of twelve adolescents that split a larger class into two. As a result, the more parsimonious four-class model was selected for further analyses. Furthermore, the mean posterior probabilities for the four identified classes ranged from .88 to .98 and the entropy value was .91, suggesting that the classes were separated well. The standardized scores and 95 % confidence intervals for each variable included in the latent profile analysis are depicted in Figure 1 for the four group solution. The majority of adolescents fell into group 1 (n = 1,856; 80.5 %), labeled the low risk group because they scored below average on anxiety (M = 4.23, SD = 2.89), conduct problems (M = 2.05, SD = 2.02), and callous-unemotional traits (M = 22.70, SD = 8.17). Adolescents in group 2 (n = 206; 8.9 %), labeled the anxious group, scored higher on anxiety (M = 13.25, SD = 2.09) compared to the low risk group, but similarly on callous-unemotional traits (M = 20.86, SD = 8.13) and conduct problems (M = 2.78, SD = 2.17) to the low risk group. Adolescents in group 3 (n = 180; 7.8 %), labeled the primary callousunemotional group, scored higher on callous-unemotional traits (M = 32.30, SD = 7.16) and conduct problems (M = 11.98, SD = 3.19) compared to the low and anxious groups, but lower on anxiety (M = 6.40, SD = 3.99) compared to the anxious group. Finally, adolescents in group 4 (n = 64; 2.8 %), labeled the secondary callousunemotional group, showed comparable levels of callousunemotional traits (M = 36.01, SD = 6.33) to the primary callous-unemotional group, although they scored higher on conduct problems (M = 18.57, SD = 6.91) compared to the rest of the identified groups. Further, youth in the secondary callous-unemotional group scored higher on anxiety (M = 9.09, SD = 4.28) compared to the primary and low risk groups, although their anxiety levels were lower than the anxious group. Post-hoc Chi square analyses revealed that boys were more likely to comprise the primary (160 boys, 20 girls; 8:1 ratio) and secondary (58 boys, 6 girls; 10:1 ratio) callousunemotional subgroups than were girls; however, girls were more likely to comprise the anxious (53 boys, 153 girls; 1:3 ratio) subgroup compared with boys. The gender ratio was more comparable for the low risk subgroup (889 boys, 967 girls), v2(2, N = 2306) = 202.88, p \ .001. The identified groups did not differ in their grade level, v2(6, N = 2306) = 11.42, p = .08, or parental education level, v2(6, N = 2306) = 3.77, p = .71, and therefore these variables were not included in further analyses. .29** .02 .05* .23** .26** .33** .21** .14** .24** -.39** 23.65 6. Impulsivity 7.TAS 8. ES 9. DIS 10.BS 11. Proactive Ag 12. Reactive Ag 13. Popularity striving 14. Peer pressure 15. Conformity Descriptives Mean 5.35 3.58 -.32** .43** .32** .36** .48** .28** .30** .09** .05* .42** .49** -.13** .23** 1 2 3.99 5.34 -.04* .24** .21** .26** .06* .01 -.03 .05* -.04 .30** .20** -.35** 1 3 4.44 19.42 .09** -.28** -.13** -.12** -.07* .01 .01 -.01 .06* -.14** -.02 1 4 .39** .43** .27** .33** .24** .23** .06* .02 .59** 3.40 4.13 -.20** 1 5 .15** .43** .33** .32** .27** .21** .27** .19** 2.85 4.87 -.28** 1 6 .08* .03 .11** .02 .01 .16** .29** 2.63 6.05 -.10** 1 7 1.65 4.56 -.13** .11** .02 .12** .13** .17** .25** 1 8 2.34 4.10 -.28** .29** .20** .31** .33** .47** 1 9 1.83 3.09 -.27** .15** .13** .27** .36** 1 10 3.84 2.79 -.21** .29** .25** .60** 1 11 4.11 8.08 -.23** .29** .22** 1 12 .98 1.02 -.03 .62** 1 13 .56 .98 -.12** 1 14 .62 2.20 1 15 * p \ .05; ** p \ .01 CU callous-unemotional, CP conduct problems, TAS thrill and adventure seeking, ES experience seeking, DIS disinhibition, BS boredom susceptibility, Ag aggression; Peer pressure susceptibility to peer pressure 8.72 .32** 5. Narcissism SD -.23** 4. Self-esteem .40** -.01 2. CP 3. Anxiety 1 1. CU Traits 1 Table 1 Descriptive statistics and correlations among the main study variables Author's personal copy J Youth Adolescence (2013) 42:964–979 971 123 Author's personal copy 972 J Youth Adolescence (2013) 42:964–979 Table 2 Model fit statistics for the latent profile analysis Classes BIC AIC Entropy LMR 1 43,788.21 43,753.75 N/A N/A 2 42,035.31 41,977.87 .98 p \ .001 3 41,490.45 41,410.04 .96 p \ .05 4 41,354.80 41,251.42 .91 p < .05 5 41,837.03 41,963.38 .89 p = .35 Values in bold indicate the optimal number of groups to retain for analysis 3.50 Anxiety 3.00 Z- scores 2.50 CP CU 2.00 1.50 1.00 .50 .00 -.50 -1.00 Low risk (80.5%) Anxious (8.9%) Primary CU (7.8%) Secondary CU (2.8%) the overall sensation seeking measure using ANOVA. Findings shown in Table 3 suggested that the primary and secondary callous-unemotional subgroups scored higher on sensation seeking compared to the low risk and anxious subgroups, but did not differ significantly from each other. Gender differences suggested that boys reported higher sensation seeking than girls, F(1, 2306) = 8.11, p \ .01. MANOVA results comparing subgroups on aggression types was significant [Wilks’ Lambda = .86, F(6, 4594) = 60.47, p \ .001]. The secondary callous-unemotional subgroup scored higher on reactive aggression compared with the primary callous-unemotional subgroup and the other two subgroups. The primary callousunemotional subgroup scored higher on reactive aggression than the anxious group, which scored higher than the low risk group (S [ P [ A [ L). Both callous-unemotional subgroups scored higher on proactive aggression than the low callous-unemotional groups, and the secondary callous-unemotional group scored higher on proactive aggression compared to the primary callous-unemotional group. Gender differences [Wilks’ Lambda = .99, F(2, 2297) = 13.21, p = .01] further suggested that boys scored higher on proactive aggression than girls. Groups Fig. 1 Z-scores and confidence intervals across subgroups identified using latent profile analysis. CU callous-unemotional; CP conduct problems Validating the Identified Groups As depicted in Table 3, MANOVA findings comparing the identified groups on self-esteem, narcissism and impulsivity suggested main effects for groups [Wilks’ Lambda = .86, F(9, 5588.01) = 39.33, p \ .001]. Anxious and secondary callous-unemotional groups scored lower on self-esteem compared with the primary callous-unemotional and low risk groups. The two callous-unemotional subgroups reported significantly higher rates of impulsivity and narcissism compared with the low risk and anxious subgroups, although the secondary callous-unemotional subgroup scored higher on narcissism compared to the primary callous-unemotional subgroup. The anxious group scored higher on impulsivity compared with the low risk group. MANOVA results comparing subgroups on different subscales of sensation seeking suggested main effects for gender [Wilks’ Lambda = .99, F(4, 2286) = 5.01, p \ .001] and group [Wilks’ Lambda = .96, F(12, 6048.48) = 6.62, p \ .001]. Boys scored higher on the Thrill and Adventure Seeking and Disinhibition subscales than girls. There were no significant differences between callous-unemotional subgroups; however, they both scored higher on disinhibition and boredom susceptibility compared with low callous-unemotional subgroups. We further compared identified groups on 123 Comparing Groups on Social Influences MANOVA results comparing subgroups on measures of general conformity, susceptibility to peer pressure, and popularity striving suggested main effects for gender [Wilks’ Lambda = .98, F(3, 2296) = 14.37, p \ .001], groups [Wilks’ Lambda = .92, F(9, 5588.01) = 22.04, p \ .001], and a significant gender by group interaction [Wilks’ Lambda = .98, F(9, 5588.01) = 3.59, p \ .001]. Boys reported higher levels of susceptibility to peer pressure and popularity striving than girls. The secondary callous-unemotional subgroup scored significantly higher on susceptibility to peer pressure and popularity striving compared with the primary callous-unemotional subgroup. Both high callous-unemotional subgroups scored significantly higher on susceptibility to peer pressure and popularity striving, but lower on general conformity/obedience, compared with low callous-unemotional groups. According to the identified gender by group interaction shown in Fig. 2, boys, but not girls, in the secondary callousunemotional subgroup reported greater susceptibility to peer pressure compared with the rest of the sample. Discussion The present study aimed to determine whether community boys and girls with callous-unemotional traits are a heterogeneous population similar to offending youth and Author's personal copy J Youth Adolescence (2013) 42:964–979 973 Table 3 Comparisons between the identified groups F-value df p g2 Low risk (n = 1,856) Anxious (n = 206) Primary CU (n = 180) Secondary CU (n = 64) 19.90(.10)a 16.65(.30)b 18.70(.32)a 16.69(.54)b 46.02 3 .00 .06 a a b 10.83(.38)c 173.11 3 .00 .18 Variables Self-esteem Narcissism 3.60(.07) Impulsivity 4.42(.06)a 5.80(.19)b 7.28(.20)c 8.00(.33)c 103.22 3 .00 .12 a a a 5.89(.33)a 1.39 3 .24 .00 4.28(.21) 7.04(.23) TAS 6.07(.06) ES 4.51(.04)a 4.73(.12)a 4.83(.12)a 4.70(.20)a 3.15 3 .02 .01 DIS 3.92(.05)a 3.69(.16)a 5.86(.17)b 5.59(.86)b 50.55 3 .00 .06 BS 2.95(.04)a 2.89(.12)a 4.24(.13)b 4.64(.22)b 45.47 3 .00 .06 16.44(.12)a 16.86(.42)a 20.70(.62)b 20.31(1.11)b 8.37 3 .00 .02 a a b c Sensation seeking 5.77(.18) 6.30(.19) Proactive Ag 2.20(.07) 301.64 3 .00 .28 Reactive Ag Popularity striving 8.35(.09)a .95(.01)a 10.75(.26)b 1.14(.04)a 12.52(.27)c 1.32(.05)b 13.84(.46)d 1.80(.08)c 126.11 58.15 3 3 .00 .00 .14 .07 .90(.01)a 1.13(.04)b 1.37(.04)c 1.89(.07)d 117.63 3 .00 .13 b b a 1.78(.08)a 61.77 3 .00 .07 Peer pressure Conformity 2.26(.01) 2.61(.19) 2.18(.04) 7.09(.20) 1.69(.05) 9.76(.35) Susceptibility to peer pressure Estimated marginal means (SE); Different superscripts (a,b,c) denote significant differences between groups in post hoc pairwise comparisons. CU callous-unemotional, CP conduct problems, TAS thrill and adventure seeking, ES experience seeking, DIS disinhibition, BS boredom susceptibility, Peer Pressure = Susceptibility to Peer Pressure Groups Fig. 2 Gender by group interaction effects including 95 % confidence intervals. CU callous-unemotional; CP conduct problems psychopathic adults (e.g., Hicks et al. 2004; Kimonis et al. 2012a, b). It aimed to combine two separate but parallel lines of research highlighting the importance of the cooccurrence of callous-unemotional traits and conduct problems, on the one hand, and the heterogeneity of callous-unemotional/psychopathic traits among antisocial populations, on the other, to determine whether community-based adolescents who show variability in their levels of conduct problems can be distinguished into primary and secondary variants when levels of callous-unemotional traits are high. It also aimed to examine whether variants would differ in their reports of distinct personality traits (i.e., self-esteem, narcissism, impulsivity, and sensation seeking) or could be distinguished on the basis of showing proactive or reactive forms of aggression. Furthermore, this study extends prior work by examining whether developmental factors that are relevant to antisocial and aggressive behavior in typically developing youth distinctly relate to the personality profiles of primary and secondary callousunemotional variants. In this respect, this research contributes four key findings. First, using a rigorous clustering approach, we successfully identified community-based primary and secondary callous-unemotional variants showing characteristics consistent with theory and prior empirical work conducted with adult and juvenile offenders (e.g., Vassileva et al. 2005; Vaughn et al. 2009), further supporting the idea that the construct of psychopathy is not unitary in adolescence. Second, callous-unemotional variants showed important differences on several social influence factors relevant to adolescent development, namely susceptibility to peer pressure and popularity striving. Third, secondary variants were distinguished by lower selfesteem in combination with greater narcissism, whereas primary variants displayed higher self-esteem. Fourth, we identified gender differences in prevalence rates for youth in the primary and secondary callous-unemotional variant subgroups, although boys and girls were relatively indistinguishable phenotypically. Our findings are placed in the context of the broader literature below. The most marked difference between adolescent callous-unemotional variants was in their levels of conduct problems. Both groups of youth scoring high on callousunemotional traits showed high levels of conduct problems, consistent with Karpman’s (1941) perspective that psychopathy variants are phenotypically indistinguishable. 123 Author's personal copy 974 However, with respect to the number of conduct problems symptoms that they reported, the proportionally smaller group of community-based secondary callous-unemotional variants reported levels approximately 1.5 standard deviations higher than primary variants, and almost three standard deviations greater on average compared with low risk youth. Similarly, secondary variants also reported the greatest levels of aggression, consistent with prior research with adult and male juvenile offender samples (e.g., Hicks et al. 2004; Kimonis et al. 2011). Anxiety was a second chief distinction between primary and secondary variants in this study, consistent with theoretical conceptualizations (Blackburn 1975; Karpman 1941, 1948a, b). The robustness of this finding—across several studies using various methods and samples—suggests that anxiety is important for distinguishing this taxonomy among adults and youth alike (e.g., Blackburn 1975; Hicks et al. 2004; Skeem et al. 2007; Vaughn et al. 2009). Similar to Swogger and Kosson’s (2007) and others’ findings, primary variants exhibited lower levels of anxiety compared with secondary variants that exhibited high levels that were close to one standard deviation above the sample mean. Interestingly, although anxiety is not strongly associated with callousunemotional traits (Frick and Ellis 1999), which is in agreement with the non-significant correlation between anxiety and callous-unemotional traits found in the current study (r = -.01), anxiety is an important subtyping variable for identifying different callous-unemotional variants. These findings expand upon a robust research base supporting the importance of callous-unemotional traits to distinguishing a more severe group of antisocial youth who show greater conduct problems and proactive and reactive aggression (Frick et al. 2003a, 2005), and suggest that within this group the additional presence of comorbid anxiety problems might further distinguish those youth with markedly more severe and aggressive conduct problems. Our finding that secondary callous-unemotional variants showed significantly greater levels of both proactive and reactive forms of aggression relative to primary variants was contrary to our hypotheses. However, reactive versus proactive forms of aggression have poorly distinguished psychopathy variants in prior research as well (see Skeem et al. 2003), and in hindsight it is likely that the presence of proactive aggression is what distinguishes youth with callous-unemotional/psychopathic traits from antisocial youth without these traits, as prior research suggests (Frick et al. 2003a), irrespective of whether the youth is classified as a primary or secondary variant. What this study was not able to address is to what extent the small subpopulation of secondary callous-unemotional variants are victims of trauma (i.e., victimization, violence exposure) as theory suggests (Karpman 1948a, b; Porter 1996), which recent research has uncovered as one 123 J Youth Adolescence (2013) 42:964–979 mechanism through which youth high on callous-unemotional traits come to express their antisocial tendencies in aggressive ways (Howard et al. 2012). In contrast, these authors suggest that high callous-unemotional youth not exposed to violent models will be likely to offend in nonviolent ways, such as engaging in property crimes. It will be important for future research to uncover whether exposure to violence (e.g., domestic, community violence, maltreatment) accounts for the pattern of anxious and aggressive characteristics that distinguishes secondary from primary variants. Primary and secondary variants did not differ significantly in their levels of callous-unemotional traits, which is consistent with prior research (Hicks et al., 2004; Kimonis et al. 2012a, b; Vassileva et al. 2005). However, they did show important differences on several external measures; primary variants reported high levels of self-esteem, whereas high-anxious secondary variants reported lower levels of self-esteem but greater narcissism. Similarly, Kimonis et al. (2011) found higher narcissism scores among incarcerated male secondary juvenile psychopathy variants compared with primary variants, supporting consistency in findings across different methods of measurement (i.e., interview-based vs. self-report instruments). Low self-esteem has long been theorized as a risk factor for antisocial and aggressive behavior, and in combination with high narcissism suggests a possible mechanism for leading secondary variants to engage in aggressive behaviors (see Barry et al. 2003; Baumeister et al. 1996). That is, decades of research on narcissism suggests that feelings of inferiority and insecurity, defensively masked by a grandiose self-view, may explain why these youth come to aggress against others proactively in order to achieve dominance and popularity among peers (Olweus 1995; Salmivalli 2001), and also reactively to preserve and avenge potential threats to their fragile egos (i.e., threatened egotism theory, Bushman and Baumeister 1998; see also Thomaes et al. 2009). Consistently, secondary callousunemotional variants’ patterns of aggression were both reactive and proactive in nature. Moreover, poor selfesteem and high narcissism are common among maltreated youth (e.g., Vondra et al. 1989), which is identified by theoretical models as a central causal factor for distinguishing secondary variants, yielding consistent empirical support among juvenile offenders (Kimonis et al. 2011; Tatar et al. 2012; Vaughn et al. 2009). With respect to primary variants, some studies report that high levels of self-esteem also may lead youth to aggressive and antisocial acts (e.g., Thomaes et al. 2008), providing a possible explanation for their engagement in aggressive behavior. Another possibility is that primary variants are better adjusted than secondary variants. For example, Hicks et al. (2010) found that individuals in the primary psychopathy Author's personal copy J Youth Adolescence (2013) 42:964–979 subgroup were characterized by relatively normal scores on personality measures, which might reflect Cleckley’s (1976) notion of the psychopath’s ‘‘mask of sanity’’ (p. 13). A novel contribution of this study was the finding that community-based secondary callous-unemotional variants showed greater susceptibility to peer pressure and popularity striving than primary variants. Consistent with their greater levels of conduct problems and aggression, Allen et al. (2006) reported a significant association between high susceptibility to peer pressure, low self-esteem and high antisocial behavior (Bamaca and Umana-Taylor 2006). Although our findings contradict Kerr et al.’s (2011) proposal that the higher adolescents are on psychopathic traits, the less they seem to be influenced by others, they do suggest that adolescents high on callous-unemotional traits and anxiety are particularly susceptible to negative peer influences and desperately strive to be popular. A significant gender by group interaction indicated that boys in the secondary callous-unemotional subgroup were more susceptible to peer pressure compared to girls. As a result, boys with high scores on conduct problems, callousunemotional traits, and anxiety are at heightened risk to be influenced by their peers during adolescence, which might relate to their greater engagement in antisocial behaviors. Because this is the first study that compares callousunemotional variants on peer status measures, these findings need to be replicated in future work. The present study uncovered a few unexpected findings. First, callous-unemotional variants did not score significantly differently from one another on measures of impulsivity and all types of sensation seeking. This finding is of note given that Karpman (1948a, b) believed that impulsivity best characterized the behavior of secondary psychopathic individuals, whereas he described primary psychopaths as carrying out their actions in a calm and purposeful way. Consistently, among an incarcerated adolescent male offender sample (N = 373), Kimonis et al. (2012a, b) found that high-anxious secondary variants of youth scoring high on the Youth Psychopathic Traits Inventory (YPI; Andershed et al. 2002) (n = 43) scored significantly higher on its impulsivity scale compared with lower anxious primary variants (n = 122), but not significantly different on its grandiose-manipulative scale. However, whereas some prior studies document higher impulsivity scores among adult secondary variants (Hicks et al. 2004), others do not (Skeem et al. 2007). Further, agreeing with our findings, Ray et al. (2009) found that both primary and secondary psychopathy variants are associated with sensation seeking. Whereas the impulsive behavior of secondary variants may result from high urgency and attempts to reduce the intensity of one’s experience of negative affect (Lynam and Miller 2004), the impulsive behavior characterizing primary variants may 975 result from their lack of inhibition to aversive stimuli, insensitivity to cues of punishment, and reward oriented behavior (Frick et al. 2003b). Another unexpected, yet logical, finding was that the latent profile analysis identified a fourth subgroup of youth scoring low on callous-unemotional traits that were distinguished primarily by high anxiety levels, higher impulsivity and reactive aggression scores and lower self-esteem in comparison with low-risk youth. This group was comprised of a proportionately greater number of girls than boys, which might explain the failure to identify this subgroup in prior juvenile subtyping studies that focused predominately on male samples. However, Swogger and Kosson (2007) similarly found a high anxious group when clustering their full sample of male inmates, which is typically not identified when only including high psychopathy scoring individuals in analyses. More in line with expectations and prior research (Fontaine et al. 2011; Rowe et al. 2010), both callous-unemotional variants exhibited more negative outcomes relative to low risk youth who exhibited the lowest levels of conduct problems, anxiety, narcissism, impulsivity, popularity striving, and susceptibility to peer pressure. Gender Differences By using a large nationally representative sample of community adolescent boys and girls, we were able to identify gender differences in rates of primary and secondary callous-unemotional traits with co-occurring conduct problems. A higher percentage of boys than girls was identified in both the primary and secondary callous-unemotional subgroups, which is in agreement with prior work showing that adolescent boys are at higher risk than girls to show co-occurring callous-unemotional traits and conduct problems (Fanti 2013). The lower percentage of girls identified in the high callous-unemotional groups might be due to gender differences in socialization experiences, as those of girls are more likely to promote empathic sensitivity (Zahn-Waxler 2000). Consistent with evidence that adolescent girls are more likely to experience anxiety than boys (Lewinsohn et al. 1998), a higher percentage of girls than boys were identified in the anxious low callousunemotional group. Although a gender by group interaction was identified in relation to the susceptibility to peer pressure measure, it is important to consider the absence of such interactions at the phenotypic level for the majority of individual and social outcomes across the identified groups. This suggests that boys and girls in the primary and secondary callous-unemotional subgroups showed similar phenotypic manifestations of personality traits, aggressive behaviors, and social influence factors relevant to adolescent development. However, a number of mean level 123 Author's personal copy 976 differences were identified, with boys reporting greater sensation seeking, susceptibility to peer pressure, popularity striving, and proactive aggression than girls. Indeed, boys prefer more novel and dangerous activities (Crapanzano et al. 2010), are more susceptible to peer pressure (Adler and Adler 1998), and are more likely to engage in proactive aggression (Fanti et al. 2009) compared with girls. Strengths and Limitations The study findings must be considered within the context of some limitations. First, all constructs were assessed using adolescents’ self-report, which may have inflated correlations due to shared method variance, or led to possible underreporting of undesirable characteristics and behaviors (Pakaslahti and Keltikangas-Jarvinen 2000). However, recent research comparing self- and parentreports of callous-unemotional traits among adolescents revealed that there may be bias in caregiver responses, and that callous-unemotional traits might be more reliably assessed using self-report or interview measures during adolescence, which tend to be significantly correlated (Fink et al. 2012). Moreover, the validity of self-report measures of psychopathic and other personality traits tends to increase with age, and the validity of parent- and teacherreports is lowest during adolescence (Frick et al. 2010). Second, we did not assess childhood abuse and other traumatic experiences that have been found to be relevant to distinguishing psychopathy variants in offender populations (e.g., Kerr et al. 2011). As a result, we were unable to evaluate whether similar theorized causal factors may be in operation for the less pathological community youth. Third, in the current study we used the narcissism scale of the APSD that assesses more maladaptive (entitlement, exploitativeness, exhibitionism) than adaptive (leadership, authority, self-sufficiency) traits; however future studies need to consider these different dimensions of narcissism (see Barry et al. 2003) in relation to primary and secondary callous-unemotional variants. Notwithstanding these limitations, the study also has important strengths. Notably, it makes use of a large nationally representative study sample, which allowed for the use of rigorous latent profile analysis, and the collection of data from both boys and girls, enabling the investigation of gender differences and gender by group interactions. Additionally, the current study was conducted in a cultural group that has not been the focus of research on callousunemotional traits. This is also the first study to be conducted in a community sample of youth to identify primary and secondary adolescent psychopathy variants. As such, it supports the contention that primary and secondary callous-unemotional variants can be identified across cultures 123 J Youth Adolescence (2013) 42:964–979 and in both community and incarcerated adolescent samples. Furthermore, the variables measured in the current study extended the association of primary and secondary callous-unemotional variants to social influence factors relevant to adolescent development. Practical Implications Practically, in community settings the presence of callousunemotional traits may signal greater risk for severe antisocial and aggressive behavior when they co-occur with anxiety than when they appear alone. If the goal is to decrease antisocial behavior, the secondary variant is the most appropriate group to target with intervention efforts. Karpman (1948b) believed that secondary variants ‘‘are amenable to psychotherapeutic treatment and therefore offer a far more hopeful outlook than is currently given to the [primary] psychopathic cases’’ (p. 533). This hypothesized potential for change in response to environmental influences highlights the importance of focusing intervention efforts and resources on this small subgroup of antisocial youth (\3 %). Furthermore, evidence for their greater susceptibility to peer influences suggests that establishing autonomy with peers may be beneficial for secondary variants, which might decrease their engagement in deviant behavior (Allen et al. 2006). Strengthening their self-esteem and reducing grandiosity can lessen youths’ vulnerability to ego threats, and reduce their potential for aggressive behavior (Thomaes et al. 2009). Another possibility is to focus efforts on alleviating their pathological anxiety by implementing evidence-based cognitivebehavioral treatments. If further research is able to establish a link between secondary callous-unemotional traits and trauma among community youth that is supported among offender populations, trauma-focused interventions may be important to future intervention research with this population. Current findings also provide information on common risk factors associated with primary and secondary callous-unemotional variants. Importantly, interventions that promote executive functioning and empathic responding might be successful for reducing problem behaviors for both primary and secondary callous-unemotional variants. In closing, adolescents with callous-unemotional/psychopathic traits are heterogeneous with respect to co-occurring conduct problems and internalizing psychopathology. Appreciating these distinctions is likely to improve the field’s understanding of the development, identification, and treatment of these traits that are relevant to a population of youth at risk for a severe and stable pattern of impairment across the lifespan. Acknowledgments This work was supported by the University of Cyprus (Internal Research Grant awarded to the first author). Author's personal copy J Youth Adolescence (2013) 42:964–979 Author Contributions KF and CD conceived of the study, participated in its design and coordination and performed the measurement; KF, CD, and EK participated in the statistical analysis, interpretation of the data and drafted the manuscript. All authors read and approved the final manuscript. References Adler, P. A., & Adler, P. (1998). Peer power: Preadolescent culture and identity. New Brunswick, NJ: Rutgers University Press. Allen, J. P., Porter, M. R., & McFarland, F. C. (2006). Leaders and followers in adolescent close friendships: Susceptibility to peer influence as a predictor of risky behavior, friendship instability, and depression. Development and Psychopathology, 18, 155–172. Allen, J. P., Porter, M. R., McFarland, F. C., Marsh, P., & McElhaney, K. B. (2005). The two faces of adolescents’ success with peers: Adolescent popularity, social adaptation, and deviant behavior. Child Development, 76, 747–760. 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He received his doctorate in Developmental Psychology from Georgia State University. His major research interests include the development of antisocial behavior, and how biological, individual and social risk and protective factors are associated with the development of aggressive and violent behavior. Chara A. Demetriou holds an MA in school psychology from the Department of Psychology, University of Cyprus, and she is working toward her MSc degree in child and adolescent Mental Health at the Institute of Child Health, University College London. Her major research interests focus on child and adolescent antisocial behavior. Eva R. Kimonis is a Senior Lecturer in the School of Psychology at the University of New South Wales. She received her doctorate in Applied Developmental Psychology from the University of New Orleans. Her program of research focuses on risk factors for the development of psychopathy and violent behavior, with special interest in the role of childhood abuse experiences and emotional processing. 123
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