Oppositional Defiant Disorder Symptoms in Relation to
Psychopathic Traits and Aggression Among Psychiatrically
Hospitalized Children: ADHD Symptoms as a Potential
Stephen P. Becker1*, Aaron M. Luebbe1, Paula J. Fite2, Leilani Greening3, and Laura Stoppelbein4,5
1Department of Psychology, Miami University, Oxford, Ohio
2Clinical Child Psychology Program, University of Kansas, Lawrence, Kansas
3Department of Psychiatry and Human Behavior, University of Mississippi Medical Center, Jackson, Mississippi
4Department of Psychology, University of Alabama at Birmingham, Birmingham, Alabama
5Glenwood Autism and Behavioral Health Center, Birmingham, Alabama
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Oppositional defiant disorder (ODD) is associated with elevated rates of psychopathic traits and aggression. However, it remains
proactive,reactiveaggression)inalargesampleofchildreninanacutepsychiatricinpatientfacility(n ¼ 699;ages6–12).Multiple
predicting narcissism. In addition, for a subset of the full sample for whom data were available (n ¼ 351), ADHD symptoms
exacerbated the relation between ODD symptoms and both reactive and proactive aggression. These results suggest that ADHD
symptoms tend to have a negative effect on the relation between ODD symptoms and markers of antisociality among children
receiving acute psychiatric care. Aggr. Behav. 9999:XX–XX, 2013. © 2013 Wiley Periodicals, Inc.
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Keywords: attention‐deficit/hyperactivity disorder; callous‐unemotional traits; comorbidity; narcissism; proactive aggression;
psychopathy; reactive aggression
Psychopathy is defined by a range of affective,
interpersonal, and behavioral characteristics, including
shallow affect, lack of guilt, glibness, superficial charm,
to punishment (Cleckley, 1941; Hart & Hare, 1997;
Lynam & Gudonis, 2005). Compared to criminal
offenders without psychopathic traits, offenders with
psychopathic traits are responsible for a disproportionate
number of crimes, commit more violent and aggressive
behavior (Hart & Hare, 1997; Hemphill, Hare, &
Wong, 1998; Salekin, Rogers, & Sewall, 1996).
Research on psychopathy in adults has been extended
O’Brien, Wootton, & McBurnett, 1994). Examining
psychopathic traits in youth is important given its
increasingly prominent role in conceptualizations of
childhood antisocial behavior, especially since callous‐
unemotional (CU) traits in particular may be useful in
identifying a distinct subset of persistently antisocial
youth (see Frick, 2012, for a review). Psychopathic traits
in youth are concurrently linked to aggression, antisocial
behavior, and peer problems (Forth, Hart, & Hare, 1990;
Kosson, Cyterski, Steuerwald, Neumann, & Walker‐
Matthews, 2002; Pardini, 2011; Pardini, Stepp, Hipwell,
Stouthamer‐Loeber, & Loeber, 2012; Piatigorsky &
Hinshaw, 2004) and also are prospectively associated
with aggression, academic problems, and overall
*Correspondence to: Stephen Becker, Department of Psychology, Miami
University, 90 North Patterson Avenue, Oxford, OH 45056. E‐mail:
Received 10 May 2012; Accepted 18 January 2013
Published online in Wiley Online Library (wileyonlinelibrary.com).
Volume 9999, pages 1–11 (2013)
© 2013 Wiley Periodicals, Inc.
impairment, as well as the severity and persistence of
antisocial behaviors (Asscher et al., 2011; Byrd, Loeber,
& Pardini, 2012; Dadds, Fraser, Frost, & Hawes, 2005;
Kahn, Byrd, & Pardini, 2012; McMahon, Witkiewitz,
Kotler, & Conduct Problems Prevention Research
Group, 2010; Pardini & Fite, 2010; Pardini et al.,
2012; Piatigorsky & Hinshaw, 2004). Thus, there are
clear adverse correlates and longitudinal outcomes
associated with the presence of these traits early in
development. Hence, an examination of these character-
istics among at‐risk children for whom prevention and
intervention efforts may be particularly beneficial has
surfaced as a priority in the field.
Conduct Problems, ADHD, and Psychopathic
Several subtype approaches for identifying the most
severe and persistent criminal offenders have been
proposed (for a review, see Frick & Marsee, 2006).
Among these approaches, Lynam (1996) proposed that
disorder (ADHD) and conduct problems such as
oppositional defiant disorder (ODD) are particularly
likely to display psychopathic traits, that is, to be
“fledgling psychopaths.” Using a developmental frame-
work, Lynam argued that for the “psychopathic‐
individual‐to‐be” (p. 224), symptoms of hyperactivity,
impulsivity, and inattention lead to early childhood
conduct problems, and thus, provides the backdrop from
which the affective, interpersonal, and behavioral
characteristics of psychopathy arise.
ADHD symptoms are associated with measures of
psychopathy (Colledge & Blair, 2001; Frick, Bodin, &
Barry, 2000; Kaplan & Cornell, 2004), and boys with
ADHD show more psychopathic traits than boys
without ADHD (Piatigorsky & Hinshaw, 2004).
However, it is possible that the correlation between
ADHD symptoms and psychopathic traits is attributable
to conduct problems such as ODD symptoms. ODD is
characterized by negativistic and defiant behaviors,
including arguing with adults, losing one’s temper, and
deliberately annoying others (American Psychiatric
Association [APA], 2000). ODD is frequently comorbid
with ADHD (APA, 2000) and is also associated with
measures of psychopathy (Fite, Greening, Stoppelbein,
& Fabiano, 2009; Kosson et al., 2002; Rogers,
Johansen, Chang, & Salekin, 1997; Salekin, Neumann,
Leistico, DiCicco, & Duros, 2004; Waschbusch &
Willoughby, 2008). As such, studies must not only
examine the relation between ADHD symptoms and
psychopathic traits, but also include measures of
conduct problems and, especially, examine whether
conduct problems and ADHD symptoms have a
multiplicative, interactive effect in predicting psycho-
To date, some empirical support has supported
Lynam’s (1996) hypothesis. For example, Johansson,
Kerr, and Andershed (2005) had violent male adult
offenders report retrospectively on their ADHD symp-
toms and conduct problems in childhood. Consistent
nonpsychopathic offenders, the offenders classified as
psychopaths were much more likely to have reported co‐
occurring conduct problems and ADHD symptoms in
childhood despite not being more likely to have had
either conduct problems or ADHD symptoms in
isolation. Similarly, C. T. Barry et al. (2000) found that
the percentage of children with elevated rates of teacher‐
reported CU traits were higher among clinic‐referred
youth with both ADHD and ODD/CD (57%) than youth
with ADHD‐only (37%) or clinical control youth (9%).
However, a group of children with conduct problems but
without ADHD was not included, leaving open the
ADHD symptoms are linked to psychopathic traits.
Finally, in a sample of adolescent boys, Lynam (1998)
conduct problems more closely resembled adult psycho-
paths compared to boys with only attention or conduct
problems. Specifically, although the co‐occurring group
did not differ from the conduct problems‐only group on
a parent‐report measure of childhood psychopathy,
Lynam’s subtype distinction was generally supported
across laboratory tasks assessing a reward‐dominant
response style (using card‐playing and delay of gratifica-
tion tasks) and youth self‐reports of delinquency.
Other studies have not supported Lynam’s (1996)
proposed subtype hypothesis. Abramowitz, Kosson, and
retrospective self‐reports of conduct problems and
ADHD symptoms in childhood each predicted psychop-
athyscores.However, the influenceofADHD symptoms
on psychopathy was largely accounted for by conduct
problems, and no evidence was found for a significant
ADHD ? conduct problems interaction in predicting
psychopathy. Similar findings have emerged when
testing Lynam’s theory in a clinic‐referred sample of
adolescent males (Hoong, Houghton, & Chapman,
2007). Sevecke, Kosson, and Krischer (2009) also
reported similar findings using a sample of incarcerated
adolescents, although results differed somewhat for
males and females. Among boys, self‐reported ADHD
symptoms no longer predicted psychopathic traits after
symptoms remained associated with psychopathic traits
after controlling for CD symptoms. Moreover, a
significant interaction of ADHD and CD symptoms
2 Becker et al.
was found for girls for the total psychopathy and
antisocial dimension of psychopathy scores, but in the
opposite direction proposed by Lynam (1996) such that
ADHD symptoms were associated with higher psychop-
athy scores at lower levels of CD symptoms but not at
higher levels of CD symptoms. Finally, Waschbusch and
Willoughby (2008) found that CU traits and ADHD
symptoms both moderated the relation between conduct
problems (i.e., ODD/CD symptoms) and school‐related
impairment, with the effect of CU traits stronger among
children with lower ADHD symptom scores. In sum,
although several studies have tested Lynam’s (1996)
proposed taxonomy, findings to date are equivocal, and
as a result, the degree to which Lynam’s model is
empirically or clinically useful remains unclear.
Dimensions of psychopathy.
multi‐faceted construct with affective, behavioral, and
interpersonal dimensions (Frick et al., 1994) and has
often been conceptualized as including CU traits,
narcissism, and impulsivity (Asscher et al., 2011; Frick
& Hare, 2001). CU traits (e.g., lack of remorse, absence
of empathy/emotionality) are considered the hallmark of
psychopathy (C. T. Barry et al., 2000; Frick & White,
2008; Frick et al., 2000) and are linked to the persistence
and severity of criminal behavior (Christian, Frick, Hill,
Tyler, & Frazer, 1997; Pardini & Fite, 2010). Given the
importance of CU traits for understanding trajectories of
antisocial behavior, a subtype for CD based on the
presence of CU traits has been proposed for the Fifth
Edition of the Diagnostic and Statistical Manual of
Mental Disorders (DSM‐5; Pardini, Frick, & Moffitt,
2010). Like CU traits, narcissism (e.g., arrogant,
grandiose presentation with concern about one’s status
over others) is associated with delinquency and recidi-
vism. Although fewer studies examining narcissism
firmconclusions,a recentmeta‐analysisby Asscheret al.
(2011) reported small effect sizes for both of these
psychopathic dimensions in relation to delinquency and
moderate effect sizes in relation to recidivism.1
Given the importance of CU traits in current models of
antisocial behavior, it is important to examine distinct
dimensions of psychopathy when testing Lynam’s
model. However, with the exception of two studies
with adolescents (Hoong et al., 2007; Sevecke et al.,
2009), Lynam’s (1996) subtype hypothesis has not yet
been examined across dimensions of psychopathic traits
with youths. Hence, the goal of the present study was to
examine Lynam’s subtype hypothesis in relation to both
Psychopathy is a
CU traits and narcissism among children with receiving
acute, inpatient psychiatric care.
ODD, ADHD, and Aggression
As noted, psychopathic traits are linked to elevated
rates of aggression. Two often‐discussed and empirically
validated subtypes of aggression are reactive aggression,
which occurs in response to threat or provocation (i.e.,
“hot‐blooded” aggression), and proactive aggression,
which is planful, goal‐directed, and motivated by
external reward (i.e., “cold‐blooded” aggression; Dodge
& Coie, 1987; Fite, Colder, & Pelham, 2006; Vitaro &
Brendgen, 2011). Both CU traits and narcissism have
been linked to both proactive and reactive aggression
(T. D. Barry et al., 2007; Kimonis et al., 2008; Kerig &
Stellwagen, 2010; Vitacco, Neumann, Caldwell, Leis-
tico, & Van Rybroek, 2006).
Therefore, in addition to examining whether ADHD
symptoms exacerbated the relation between ODD
symptoms and psychopathic traits, we also sought to
test whether ADHD symptoms exacerbated the relation
between ODD symptoms and aggression. ODD symp-
toms are strongly associated with both proactive and
reactive aggression (Becker, Luebbe, Stoppelbein,
Greening, & Fite, 2012; Cunningham & Boyle, 2002;
Waschbusch & Willoughby, 2008), and ADHD is also
linked to aggression, although more closely to reactive
than to proactive aggression (Dodge, Lochman, Harnish,
Bates, & Pettit, 1997; Waschbusch, Willoughby, &
Pelham, 1998). As such, it is perhaps not surprising that
at least some research supports the possibility that,
compared to their peers, youth who display both conduct
problems and ADHD have poorer social skills generally
(Becker, Luebbe, & Langberg, 2012; Gresham, Lane, &
Lambros, 2000) and also display elevated rates of
aggression specifically (Carlson, Tamm, & Gaub, 1997;
Roberts, 1995; Waschbusch et al., 2002). Examining
proactive and reactive subtypes of aggression in parallel
to the psychopathy dimensions of CU traits and
narcissism is important given that aggressive behaviors
are harmful, observable behaviors that may contribute to
psychiatric hospitalization and are often the focus of
The Present Study
Despite the substantial influence of Lynam’s (1996)
theory on recent investigations of psychopathic traits in
childhood and adolescence, few studies have directly
examined whether ADHD and ODD symptoms interact
in contributing to elevated rates of psychopathic traits
and aggression. Further, extant studies examining the
interrelations of ADHD and ODD symptoms to
psychopathy have primarily used samples of adolescents
1Of note, impulsivity (e.g., acting without thinking, engaging in risky
activities) has also been linked to delinquency and recidivism (Asscher
et al., 2011), but given the clear overlap with DSM‐IVADHD symptoms is
not considered in the current study as a distinct facet of psychopathy.
ADHDþODD, Psychopathic Traits, and Aggression3
or adults. Studies with younger children are needed to
identify the children for whom early intervention and
prevention efforts may be most effective. The one study
to date that has tested Lynam’s proposed taxonomy in a
sample of clinic‐referred children did not include a
group of children who displayed conduct problems
without co‐occurring ADHD (C. T. Barry et al., 2000),
and so it remains unclear whether it is the combined
presence of ADHD and conduct problems, as opposed to
conduct problems regardless of the presence or absence
of ADHD, that is linked to higher psychopathic traits
among youth. Hence, the present study examined
Lynam’s (1996) proposed subtyping in relation to
both CU traits and narcissism and also examined
whether ADHD symptoms interact with ODD symp-
toms to increase rates of reactive and proactive
aggression. We tested this hypothesis in a large sample
of psychiatrically hospitalized children. Utilizing such a
sample is ideal given that these children have elevated
rates of psychopathology and are at risk for a range of
subsequent psychosocial difficulties while simulta-
neously being young enough to draw inferences related
to early‐onset models of psychopathic traits and
acute child psychiatric inpatient facility that provides
servicesfor 4‐ to12‐year‐oldchildren.Thetypicallength
of stay is one to 3 weeks. Children were excluded from
participation if their caregiver declined to allow the
child’s clinical data to be used in a research database or
the child (a) had experienced traumatic brain injury, (b)
was diagnosed with an autism spectrum disorder or
psychosis or had a history of traumatic brain injury, (c)
was <6 years old, or (d) was in the custody of the
children (Mage¼ 9.20, SDage¼ 1.93; 507 boys) partici-
(78.2%); the remaining were fathers (7.4%), grand-
parents (6.5%), or others (including other family
members or foster care guardians; 7.9%). For ease of
presentation, “parent” will be used hereafter. Parent‐
identified race/ethnicity of the participants was primarily
African‐American (57.5%), with 38.9% Caucasian and
2.2% Biracial. Five participants identified as Hispanic
(0.7%), and five as “other” (0.7%). Although the
socioeconomic status of individual participants was
unavailable, 84% of the children who are treated by the
the unit with a wide range of difficulties, including
aggression and suicidal ideation. For the unit, discharge
diagnoses are made by treatment team consensus, with
diagnoses by history also used in the decision‐making
the unit are diagnosed with a least one externalizing
disorder (e.g., CD, ODD, ADHD) and 20% are
diagnosed with at least one internalizing disorder (e.g.,
depression, anxiety) or another psychiatric condition
(e.g., Tourette’s syndrome, learning disorders). Approxi-
mately two‐thirds of the children are diagnosed with
more than one disorder.
ADHD and ODD symptoms.
the Child Behavior Checklist for Ages 6–18 (CBCL/6–
18) by rating on a 3‐point scale (0 ¼ not true,
1 ¼ sometimes true, 2 ¼ very true) how true each of
120 problem items was for their child. The DSM‐oriented
(APA, 2000) ADHD (7 items) and ODD (5 items)
subscales of the CBCL were used in the current study
(Achenbach & Rescorla, 2001). The ODD scale was used
to represent children’s conduct problems rather than the
CD scale given the significant overlap between CD and
aggression (i.e., 7 of the 15 CD symptoms involve
aggression; Connor, 2003) and, to a lesser degree, CU
traits (e.g., “lack of guilt”). As noted by Connor (2003),
“CD is the prototypic categorical childhood psychiatric
diagnosis associated with aggressive and related behav-
iors” (p. 67), and so ODD symptoms were used in the
present study given their (1) lack of overlap with our
outcome variables of interest, (2) salience for the age
range represented in the present study where many CD
symptoms (e.g., fire‐setting, truancy) have very low base
rates, and (3) importance as a developmental precursor to
CD, delinquency, and antisocial behavior in adolescence
and adulthood (e.g., Lahey, McBurnett, & Loeber, 2000;
Loeber, Stouthamer‐Loeber, & Raskin White, 1999). The
ADHD and ODD DSM‐oriented scales have demonstrat-
edgoodreliability(e.g.,a ? .85),andhavedemonstrated
convergent validity with parent‐report symptom scales
and discriminatory validity in relation to interview‐based
DSM‐IV diagnoses (Achenbach & Rescorla, 2001;
Nakamura, Ebesutani, Bernstein, & Chorpita, 2009).
Mean scores were computed for the ADHD and ODD
scales, and internal consistencies were .79 and .76,
20‐item parent version of the Antisocial Process
Screening Device (APSD; Frick & Hare, 2001). In the
assessment of psychopathic traits among youth, the
APSD is the most frequently‐used measure (Kotler &
McMahon, 2010), has demonstrated adequate internal
consistency (e.g., a > .65) and test‐retest reliability
(Frick & Hare, 2001), and is validated for and has been
used frequently for youth ages 6–12 (Dadds et al., 2005).
Caregivers completed the
4 Becker et al.
Usinga3‐pointscale(0 ¼ notatalltrue,1 ¼ sometimes
true,2 ¼ definitelytrue)parentsratedhowtrueeachitem
was for their child. Research supports either a two‐factor
(CU traits and narcissism/impulsivity) or three‐factor
(CU traits, narcissism, impulsivity) model of the APSD
(Daddset al., 2005;Fite et al., 2009; Frick & Hare, 2001;
Frick et al., 2000). Given the focus on ADHD symptoms
in the present study and potential overlap of ADHD
symptoms with psychopathy‐related impulsivity, the
three‐factor model was used in the present study but
the impulsivity scale was not considered. Mean scores of
the CU traits (6 items; a ¼ .64, e.g., “Does not show
emotions”) and narcissism (7 items; a ¼ .77; e.g.,
“Brags excessively about his/her abilities, accomplish-
ments, or possessions”) scales were used in the present
Parents completed Dodge and Coie’s
(1987) 6‐item measure of proactive and reactive
aggression using a five‐point response scale (1 ¼ never,
5 ¼ always) regarding how often his/her child engaged
in particular aggressive behaviors. Separate reactive
aggression (3 items; a ¼ .85; e.g., “When my child has
been teased or threatened, she or he gets angry easily and
strikes back”) and proactive aggression (3 items;
a ¼ .82; e.g., “My child threatens or bullies others in
order to get his or her way”) subscales were calculated.
Factor analytic work supports the proactive–reactive
aggression distinction using this measure (Vitaro &
Brendgen, 2011). This measure has also demonstrated
excellent reliability (e.g., a > .90) and is valid for use
with children between ages 6 and 12 (Dodge et al., 1997;
Waschbusch et al., 1998).
The Dodge and Coie (1987) measure was added to the
scores are only available on a subset of children
(n ¼ 351). It is noted, however, that children with and
without aggression data did not differ on ADHD
symptoms, ODD symptoms, narcissism, or CU traits,
ts(697) ¼ ?1.08to 1.29,p > .15.Hence,thesubsample
of children with aggression data is considered a
The hospital IRB approved all procedures. During
the child’s standard admission process, parents were
asked to provide consent for their child’s clinical data
to be included in an ongoing research database. Parents
were informed that their child’s clinical care would not
be contingent upon nor be affected by participation,
and no incentive for participation was offered. Once
written consent was obtained, parents completed a
standard battery of measures that included the study
measures. Staff members were available to answer any
First, the range, skew, and kurtosis values were
examined for each of the psychopathy and aggression
subscales. Each subscale demonstrated the maximum
range possible, and the absolute values of skew and
kurtosis were below 1.5. As shown in Table I, bivariate
symptoms were significantly associated with the psy-
consistently having stronger correlations (r ¼ .25–.52)
than ADHD symptoms (r ¼ .19–.44). Steiger’s z‐tests
for dependent correlations indicated that, as expected
given previous research (e.g., Abramowitz et al., 2004;
Colledge & Blair, 2001; Fite et al., 2009; Frick et al.,
2000), both ODD and ADHD symptoms were more
strongly correlated with narcissism than with CU traits,
z ¼ 7.06 and 6.27, respectively, P < .001. Also, both
ODD and ADHD symptoms were more strongly
correlated with reactive than with proactive regression,
z ¼ 2.40 and 2.01, respectively, P < .05.
Linear regression analyses were conducted to test if
ADHD symptoms moderated the relation between ODD
symptoms andpsychopathic traits and/oraggression. For
the moderation analyses, each of the four outcome
variables (i.e., narcissism, CU traits, reactive aggression,
symptoms. Age, sex, and race were included as
covariates in all analyses. ODD and ADHD scores
were highly correlated (r ¼ .59, P < .001) and thus,
were mean‐centered prior to creating interaction terms to
reduce multicollinearity. Next, models were re‐run with
the ODD ? ADHD interaction included as a predictor.
Results of the regression analyses are summarized in
Table II. For main‐effects models, ODD symptoms were
positively associated with all psychopathy and aggres-
sion outcomes, over and above child demographics (i.e.,
race, sex, and age) and ADHD symptoms. ADHD
symptoms were significantly positively associated with
narcissism above and beyond child demographics and
ODD symptoms, but in contrast to ODD symptoms were
not significantly associated with CU traits, reactive
significant ODD ? ADHD interaction was not foundfor
narcissism (indicating that both ODD and ADHD
symptoms had a significant, additive effect on narcis-
sism), significant or marginally significant ODD ?
ADHD interactions were found for each of the other
outcome variables of interest.
First, the interaction term was marginally significant in
predicting CU traits, t ¼ 1.87, P ¼ .06. This interaction
ADHDþODD, Psychopathic Traits, and Aggression5
TABLE I. Descriptive Statistics and Intercorrelations of Study Variables
4. ODD symptoms
5. ADHD symptoms
7. CU traits
8. Reactive aggression
9. Proactive aggression
Note. ADHD, attention‐deficit/hyperactivity disorder; CU, callous‐unemotional; ODD, oppositional defiant disorder.
aFor race, non‐Caucasian ¼ 0, Caucasian ¼ 1.
bFor sex, boys ¼ 0, girls ¼ 1.
cAge is calculated in years.
*P <. 05;**P <. 01;***P <. 001.
TABLE II. Regression Analyses Predicting Aggression and Psychopathic Traits from ODD Symptoms, ADHD Symptoms, and
Their Interaction Controlling for Demographic Variables
Main effects modelModeration model
Independent variablesb SE
ODD ? ADHD
ODD ? ADHD
ODD ? ADHD
ODD ? ADHD
Note. ADHD, attention‐deficit/hyperactivity disorder symptoms. ODD, oppositional defiant disorder. For race, non‐Caucasian ¼ 0, Caucasian ¼ 0. For sex,
boys ¼ 0, girls ¼ 1. Age is calculated in years.
†P < .06;*P < .05;**P < .01;***P < .001.
F(5, 690) ¼ 64.43; R2¼ .32
F(5, 690) ¼ 10.77; R2¼ .07
F(5, 343) ¼ 20.90; R2¼ .23
F(5, 343) ¼ 11.56; R2¼ .14
F(6, 689) ¼ 53.95; R2¼ .32
F(6, 689) ¼ 9.59; R2¼ .08
F(6, 342) ¼ 18.65; R2¼ .25
F(6, 342) ¼ 11.14; R2¼ .16
6Becker et al.
so too did the relation between ODD symptoms and CU
traits. However, the contribution of the interaction term
was minimal, suggesting a minimal influence of the
interaction in predicting CU traits. Next, the significant
interaction terms in predicting reactive and proactive
aggression were also plotted, and are shown in Figures 2
and 3, respectively. Similar to the interaction for CU
traits, ADHD symptoms exacerbated the relation
The purposes of the present study were to test whether
the co‐occurrence of ADHD and conduct problems
relates to elevated rates of psychopathic traits in
childhood (i.e., Lynam’s  subtype model), and to
also examine whether ADHD symptoms exacerbate the
relation between ODD symptoms and aggression in a
sample of children receiving inpatient psychiatric care.
Few studies have directly tested Lynam’s hypothesis
among children and results to date have been mixed. In
addition to testing Lynam’s model in a large sample of
psychiatrically hospitalized school‐aged children, the
present study offers a significant contribution to the
extant research given its consideration of multiple
dimensions of psychopathy (i.e., CU traits, narcissism)
and additional examination of relevant aggressive
subtypes (i.e., proactive and reactive aggression).
In terms of psychopathic traits, the present study found
mixed results in terms of Lynam’s (1996) model.
Consistent with previous research (Abramowitz et al.,
2004; Colledge & Blair, 2001; Fite et al., 2009; Frick
et al., 2000), both ODD and ADHD symptoms had a
direct, main effect on narcissism, but did not interact to
increase risk for narcissism as would be predicted by
Lynam’s theory. However, a marginal interaction effect
was found in relation to CU traits. Although conceptu-
alizations of psychopathy regularly include narcissism
and impulsivity alongside CU traits, CU traits have been
identified as being more important than the other
dimensions for identifying a subgroup of youth who
evidence particularly severe and chronic forms of
antisocial behavior (Christian et al., 1997; Frick et al.,
2003; Kahn et al., 2012). As such, CU traits have long
been considered the hallmark of psychopathy (e.g.,
Cleckley, 1941) and play an increasingly important role
in developmental models of severe and persistent
antisocial behaviors (Frick, 2012; Pardini et al., 2010;
White & Frick, 2010). Our results suggest that children
displaying both ODD and ADHD symptoms may be at
increased risk for displaying CU traits. However, even
though a marginally significant interaction was found in
the present study, it is important to note that the
interaction term had a small effect in the regression
model, and further, the full model including ODD,
ADHD,and theirinteractiondid notexplain a substantial
amountofthe variancein CUtraits. Therefore,itremains
of ODD and ADHD symptoms, efforts to identify youth
2.52 1.51 0.50
b = 1.68, p < .001
b = 1.34, p < .001
b = 1.01, p < .001
Fig. 1. ADHD symptoms moderate the relation between ODD
symptoms and CU Traits.
b = 1.47, p < .001
b = 1.19, p < .001
b = 0.92, p < .001
Fig. 2. ADHD symptoms moderate the relation between ODD
symptoms and reactive aggression.
b = 1.36, p < .001
b = 1.03, p < .001
b = 0.71, p < .001
Fig. 3. ADHD symptoms moderate the relation between ODD
symptoms and proactive aggression.
ADHDþODD, Psychopathic Traits, and Aggression7
symptoms of conduct problems or ADHD are consid-
ered. Rather, CU traits offer a unique contribution to
models of antisocial behavior that are notably distinct
from current DSM diagnoses of ADHD, ODD, and CD
(Dadds et al., 2005; Frick et al., 2000; Salekin et al.,
Although psychopathic traits and aggressive behaviors
even in childhood (see Porter & Woodworth, 2006).
Therefore, in addition to examining whether ADHD
symptoms moderated the relation between ODD symp-
toms and psychopathic traits, we also examined similar
models in relation to reactive and proactive aggression.
Previous studies have found mixed support for the
possibility that ADHD exacerbates the link between
ODD and aggression (e.g., August et al., 1996; Cunning-
ham & Boyle, 2002; Gadow & Nolan, 2002), but our
results suggest that, at least among psychiatrically
hospitalized children, the co‐occurrence of ODD and
ADHD symptoms is associated with increased risk for
both proactive and reactive aggression. Further, our
results demonstrate that ADHD symptoms are not
themselves directly linked to aggression (or CU traits)
when low levels of oppositionality are present, but are
only associated with these behaviors and traits when
children also display moderate to elevated levels of
Before discussing the implications of these findings,
several limitations of the present study are important to
note. Perhaps most importantly, only parent‐report
measures were included, which may contribute to
mono‐informant biases. It will be critical for future
studies to incorporate a more comprehensive, multi‐
methodapproach. Forexample, itis importantthat future
studies incorporate more objective, laboratory‐based
measures of psychopathy (e.g., physiological and
the covert nature of certain psychopathy dimensions
(e.g., the affective component related to CU traits).
Relatedly, DSM‐based scales of the CBCL were used in
the present study to measure ADHD and ODD
symptoms, and although validated, are limited in their
scope and do not include all DSM‐IV symptoms. Results
must therefore be interpreted in relation to continuous
Likewise, the 7‐item CBCL ADHD scale does not
sufficiently capture the separate inattentive and hyperac-
tive‐impulsive dimensions of ADHD, leaving questions
related to ADHD subtype unaddressed by our study.
Also, our use of an acute psychiatric inpatient sample
limits generalization to community and clinic‐referred
youth. Children in this study were not necessarily
hospitalized due to impairment resulting solely from
ADHD or ODD symptoms and displayed a wide range of
mental health difficulties (e.g., suicidality). Finally, the
purpose of the present study was to directly test Lynam’s
developmental models of antisocial behavior were unad-
dressed (e.g., Frick & Marsee, 2006; Frick, 2012). For
display elevated rates of CU traits may be most likely to
engage in persistent aggressive and delinquent behaviors
needed to evaluate whether such models are empirically
and clinically useful among children receiving acute
that can be drawn from our findings. First, it is clear that
children with co‐occurring ADHD and ODD symptoms
display elevated rates of aggression and, to a lesser
degree, CU traits. In considering CU traits, it is unlikely
that a subtyping approach for identifying children with
ADHD þ ODD symptoms will be useful in identifying
the “fledgling psychopath” (Lynam, 1996) given the
small effect for such an interaction in the present study.
Rather, children with these co‐occurring symptoms may
be at distinct risk, but likely not in relation to the most
concerning markers of psychopathic traits in childhood.
In addition, although a significant ODD ? ADHD
interaction was not found for narcissism, both ODD
and ADHD did individually contribute to increased
narcissism. Narcissism is itself important to consider
given its association with aggression, delinquency, and
recidivism (Asscher et al., 2011; C. T. Barry, Grafeman,
Adler, & Pickard, 2007).
Although clinic and community‐based studies report
mixed findings in terms of whether ADHD exacerbates
the aggressive behaviors of children with ODD (e.g.,
& Nolan, 2002), it is possible that exacerbation is more
likely to be consistently found among psychiatrically
hospitalized children. Hospitalized children show ele-
vated rates of aggression compared to their non‐
hospitalized peers (Pfeffer, Plutchik, Mizruchi, &
Lipkins, 1987), and aggressive children often display
both proactive and reactive aggressive behaviors (Vitaro,
Brendgen, & Tremblay, 2002). Given the strong relation
between ODD symptoms and all aggressive subtypes in
psychiatrically hospitalized children (Becker, Luebbe,
Stoppelbein et al., 2012), it appears that the co‐
occurrence of ADHD symptoms adds increased risk
for aggression in this population. As such, attending to
the co‐occurrence of such symptoms may be especially
critical in this population for reducing aggressive
behaviors. Further, high levels of ADHD symptomatol-
ogy are not ubiquitous, as our measure of ADHD
symptoms had a wide range and was not negatively
8Becker et al.
skewed. As such, even though ADHD symptoms are not
themselves the cause for admittance to a child inpatient
unit, such symptoms may still have relevance for
assessing and treating childhood aggression.
Ultimately, it is crucial to implement evidence‐based
behaviors given the potential developmental consequen-
elevated rates of psychopathic characteristics and
persistent conduct problems. Importantly, Salekin’s
(2002) review of psychopathy‐targeted treatment studies
is, essentially, an untreatable syndrome” (p. 79), inter-
ventions to treat psychopathic traits can be effective.
Salekin (2002) also found that a higher proportion of
youthbenefited from psychopathy‐targeted interventions
than adults, indicating that children in acute psychiatric
care may be responsive to well‐designed interventions.
However, most interventions specifically tailored to
treating psychopathic characteristics have been designed
for use over multiple months with juvenile justice‐
involved youth, and it may be important to consider
alternative interventions for younger children who are
not yet involved in the juvenile justice system but are at
risk for such involvement.
Examples of possible viable interventions include
Coping Power (Lochman & Wells, 2002), which was
designed to address the impulsive, aggressive behaviors
linked to deficits in social information processing and
may be particularly beneficial for children displaying co‐
occurring ADHD and ODD. Likewise, for at‐risk
children in psychiatric care, interventions that incorpo-
rate parent components in tandem with youth involve-
ment are especially warranted (Lochman & Wells, 2004;
Salekin, 2002). Hawes and Dadds (2007) found that a
subset of young boys (Mage¼ 6.29) referred for conduct
problems had decreased CU trait scores following a
parent‐training intervention. However, given the rela-
tively short length of time children are admitted to
inpatient psychiatric care, it will be important to consider
modifications to existing treatment protocols, as well as
how to feasibly include caregiver involvement and link
families to community‐based mental health services.
This will be particularly important for addressing
psychopathic traits and aggression, which may be
especially elevated among psychiatrically hospitalized
children with co‐occurring ADHD and ODD symptoms.
Abramowitz, C. S., Kosson, D. S., & Seidenberg, M. (2004). The
relationship between childhood attention deficit hyperactivity disorder
and conduct problems and adult psychopathy in male inmates.
Personality and Individual Differences, 36, 1031–1047.
Achenbach, T. M., & Rescorla, L. A. (2001). Manual for the ASEBA
school‐age forms and profiles. Burlington, VT: University of Vermont,
Research Center for Children, Youth, and Families.
mental disorders (4th ed. text revision). Washington, DC: Author.
V. I., & Yousfi, S. (2011). The relationship between juvenile
psychopathic traits, delinquency and (violent) recidivism: A meta‐
analysis. Journal of Child Psychology and Psychiatry, 52, 1134–1143.
August, G. J., Realmuto, G. M., MacDonald, A. W., III, Nugent, S. M., &
Crosby, R. (1996). Prevalence of ADHD and comorbid disorders
among elementary school children screened for disruptive behavior.
Journal of Abnormal Child Psychology, 24, 571–595.
B. R. (2000). The importance of callous‐unemotional traits for
Psychology, 109, 335–340.
Barry, C. T., Grafeman, S. J., Adler, K. K., & Pickard, J. D. (2007). The
relations among narcissism, self‐esteem, and delinquency in a sample
of at‐risk adolescents. Journal of Adolescence, 30, 933–942.
Barry,T. D.,Thompson,A.,Barry, C.T.,Lochman,J. E.,Adler,K.,&Hill,
K. (2007). The importance of narcissism in predicting proactive and
reactive aggression in moderately to highly aggressive children.
Aggressive Behavior, 33, 185–197.
Becker, S. P., Luebbe, A. M., & Langberg, J. M. (2012). Co‐occurring
mental health problems and peer functioning among youth with
attention‐deficit/hyperactivity disorder: A review and recommenda-
279–302. doi: 10.1007/s10567‐012‐0122‐y
Becker, S. P., Luebbe, A. M., Stoppelbein, L., Greening, L., & Fite, P. J.
(2012). Aggression among children with ADHD, anxiety, or co‐
occurring symptoms: Competing exacerbation and attenuation hypoth-
eses. Journal of Abnormal Child Psychology, 40, 527–542. doi:
Byrd, A. L., Loeber, R., & Pardini, D. A. (2012). Understanding desisting
and persisting forms of delinquency: The unique contributions of
disruptive behavior disorders and interpersonal callousness. Journal of
Child Psychology and Psychiatry, 53, 371–380.
Carlson, C. L., Tamm, L., & Gaub, M. (1997). Gender differences in
children with ADHD, ODD, and co‐occurring ADHD/ODD identified
in a school population. Journal of the American Academy of Child and
Adolescent Psychiatry, 36, 1706–1714.
Christian, R. E., Frick, P. J., Hill, N. L., Tyler, L., & Frazer, D. R. (1997).
Psychopathy and conduct problems in children: II. Implications of
subtyping children with conduct problems. Journal of the American
Academy of Child and Adolescent Psychiatry, 36, 233–241.
Cleckley, H. (1941). The mask of sanity. St. Louis, MO: Mosby.
Colledge, E., & Blair, R. J. R. (2001). The relationship in children between
the inattention and impulsivity components of attention deficit and
hyperactivity disorder and psychopathic tendencies. Personality and
Individual Differences, 30, 1175–1187.
Connor, D. F. (2003). Aggression and antisocial behavior in children and
adolescents: Research and treatment. New York: Guilford.
Cunningham, C. E., & Boyle, M. H. (2002). Preschoolers at risk for
attention‐deficit hyperactivity disorder and oppositional defiant
disorder: Family, parenting, and behavioral correlates. Journal of
Abnormal Child Psychology, 30, 555–569.
Dadds, M. R., Fraser, J., Frost, A., & Hawes, D. J. (2005). Disentangling
the underlying dimensions of psychopathy and conduct problems in
childhood: A community study. Journal of Consulting and Clinical
Psychology, 73, 400–410.
Dodge, K. A., & Coie, J. D. (1987). Social‐information‐processing factors
in reactive and proactive aggression in children’s peer groups. Journal
of Personality and Social Psychology, 53, 1146–1158.
ADHDþODD, Psychopathic Traits, and Aggression9
Dodge, K. A., Lochman, J. E., Harnish, J. D., Bates, J. E., & Pettit, G. S.
(1997). Reactive and proactive aggression in school children and
psychiatrically impaired chronically assaultive youth. Journal of
Abnormal Psychology, 106, 37–51.
distinguishing pure and co‐occurring dimensions of proactive and
reactive aggression. Journal of Clinical Child and Adolescent
Psychology, 35, 578–582.
Fite, P. J., Greening, L., Stoppelbein, L., & Fabiano, G. A. (2009).
Confirmatory factor analysis of the Antisocial Process Screening
Device with a clinical inpatient population. Assessment, 16, 103–114.
Forth,A.E., Hart,S.D.,&Hare,R.D. (1990).Assessmentofpsychopathy
in male young offenders. Psychological Assessment, 2, 342–344.
Frick, P. J. (2012). Developmental pathways to conduct disorder:
Implications for future directions in research, assessment, and
treatment. Journal of Clinical Child and Adolescent Psychology, 41,
Frick, P. J., Bodin, S. D., & Barry, C. T. (2000). Psychopathic traits and
Further development of the psychopathy screening device. Psycholog-
ical Assessment, 12, 382–393.
Callous‐unemotional traits and conduct problems in the prediction of
conduct problem severity, aggression, and self‐report of delinquency.
Journal of Abnormal Child Psychology, 31, 457–470.
Frick, P. J., & Hare, R. D. (2001). Antisocial process screening device:
Technical manual. North Talawanda, NY: Multi‐Health Systems.
Frick, P. J., & Marsee, M. A. (2006). Psychopathy and developmental
pathways to antisocial behavior in youth. In C. J. Patrick (Ed.),
Handbook of psychopathy (pp. 353–385). New York: Guilford.
Frick, P. J., O’Brien, B. S., Wootton, J. M., & McBurnett, K. (1994).
Psychopathy and conduct problems in children. Journal of Abnormal
Psychology, 103, 700–707.
Frick, P. J., & White, S. F. (2008). The importance of callous‐unemotional
traits for developmental models of aggressive and antisocial behavior.
Journal of Child Psychology and Psychiatry, 49, 359–375.
Gadow, K. D., & Nolan, E. E. (2002). Differences between preschool
children with ODD, ADHD, and ODD þ ADHD symptoms. Journal
of Child Psychology and Psychiatry, 43, 191–201.
Gresham, F. M., Lane, K. L., & Lambros, K. M. (2000). Comorbidity of
conduct problems and ADHD: Identification of “fledgling psycho-
paths.” Journal of Emotional and Behavioral Disorders, 8, 83–93.
555–572). New York: Guilford.
with criminal conduct. In D. Stoff, J. Breiling, & J. D. Maser (Eds.),
Handbook of antisocial behavior (pp. 22–35). New York: Wiley.
Hawes, D. J., & Dadds, M. R. (2007). Stability and malleability of callous‐
unemotional traits during treatment for childhood conduct problems.
Journal of Clinical Child and Adolescent Psychology, 36, 347–355.
Hemphill, J. F., Hare, R. D., & Wong, S. (1998). Psychopathy and
recidivism: A review. Legal and Criminological Psychology, 3, 141–
Hoong, W., Houghton, S., & Chapman, E. (2007). Relationships between
attention deficit/hyperactivity, conduct disorder, psychopathy, and
aggression: The fledgling psychopath hypothesis. In M. C. Shriner
(Ed.), Trends in attention deficit hyperactivity disorder research (pp.
99–127). New York: Nova Science.
Johansson, P., Kerr, M., & Andershed, H. (2005). Linking adult
psychopathy with childhood hyperactivity‐impulsivity‐attention prob-
lems and conduct problems through retrospective self‐reports. Journal
of Personality Disorders, 19, 94–101.
Kahn, R. E., Byrd, A., & Pardini, D. A. (2012). Callous‐unemotional traits
robustly predict future criminal offending in young men. Law and
Human Behavior, Advanceonline publication. doi: 10.1037/b0000003
Kaplan, S. G., & Cornell, D. G. (2004). Psychopathy and ADHD
in adolescent male offenders. Youth Violence and Juvenile Justice, 2,
L. C., … Morris, A. S. (2008). Assessing callous‐unemotional traits in
adolescent offenders: Validation of the inventory of callous‐unemo-
Kosson, D. S., Cyterski, T. D., Steuerwald, B. L., Neumann, C. S., &
Walker‐Matthews, S. (2002). The reliability and validity of the
Psychopathy Checklist: Youth Version (PCL:YV) in nonincarcerated
adolescent males. Psychological Assessment, 14, 97–109.
and adolescent psychopathy (pp. 79–109). New York: Guilford.
Lahey, B. B., McBurnett, K., & Loeber, R. (2000). Are attention‐deficit/
hyperactivity disorder and oppositional defiant disorder developmental
precursors to conduct disorder? In A. J. Sameroff, M. Lewis, & S. M.
Miller (Eds.), Handbook of developmental psychopathology (2nd ed.
pp. 431–446). Dordrecht, Netherlands: Kluwer Academic Publishers.
Lochman, J. E., & Wells, K. C. (2002). Contextual social‐cognitive
mediators and child outcome: A test of the theoretical model in the
Coping Power program. Development and Psychopathology, 14,
Lochman, J. E., & Wells, K. C. (2004). The Coping Power program for
preadolescentaggressiveboysand theirparents:Outcome effects at the
1‐year follow‐up. Journal of Consulting and Clinical Psychology, 72,
Loeber, R., Stouthamer‐Loeber, M., & Raskin White, H. (1999).
Developmental aspects of delinquency and internalizing problems
and their association with persistent juvenile substance use between
ages 7 and 18. Journal of Clinical Child and Adolescent Psychology,
Lynam, D. R. (1996). Early identification of chronic offenders: Who is the
fledgling psychopath? Psychological Bulletin, 120, 209–234.
Lynam, D. R. (1998). Early identification of the fledgling psychopath:
Abnormal Psychology, 107, 566–575.
Lynam, D. R., & Gudonis, L. (2005). The development of psychopathy.
Annual Review of Clinical Psychology, 1, 381–407.
McMahon, R. J., Witkiewitz, K., & Kotler, J. S. The Conduct Problems
Prevention Research Group. (2010). Predictive validity of callous‐
unemotional traits measured in early adolescence with respect to
multiple antisocial outcomes. Journal of Abnormal Psychology, 119,
Nakamura, B. J., Ebesutani, C., Bernstein, A., & Chorpita, B. F. (2009). A
psychometric analysis of the Child Behavior Checklist DSM‐oriented
scales. Journal of Psychopathology and Behavioral Assessment, 31,
Pardini, D. A. (2011). Perceptions of social conflicts among incarcerated
adolescents with callous‐unemotional traits: ‘You’re going to pay. It’s
going to hurt, but I don’t care. Journal of Child Psychology and
Psychiatry, 52, 248–255.
Pardini, D. A., & Fite, P. J. (2010). Symptoms of conduct disorder,
oppositional defiant disorder, attention‐deficit/hyperactivity disorder,
and callous‐unemotional traits as unique predictors of psychosocial
maladjustment in boys: Advancing an evidence base for DSM‐V.
Journal of the American Academy of Child and Adolescent Psychiatry,
Pardini, D. A., Frick, P. J., & Moffitt, T. E. (2010). Building an evidence
10Becker et al.
conduct disorder: Introduction to the special section. Journal of
Abnormal Psychology, 119, 683–688.
Pardini, D., Stepp, S., Hipwell, A., Stouthamer‐Loeber, M., & Loeber, R.
subtype disorder in young girls. Journal of the American Academy of
Child and Adolescent Psychiatry, 51, 62–73.
Paternite, C. E., Loney, J., & Roberts, M. A. (1995). External validation of
oppositional disorder and attention deficit disorder with hyperactivity.
Journal of Abnormal Child Psychology, 23, 453–471.
Pfeffer, C. R., Plutchik, R., Mizruchi, M. S., & Lipkins, R. (1987).
Assaultive behavior in child psychiatric inpatients, outpatients, and
Psychiatry, 26, 256–261.
Piatigorsky, A., & Hinshaw, S. P. (2004). Psychopathic traits in boys with
and without attention‐deficit/hyperactivity disorder: Concurrent and
longitudinal correlates. Journal of Abnormal Child Psychology, 32,
Porter, S., & Woodworth, M. (2006). Psychopathy and aggression. In C. J.
Patrick (Ed.), Handbook of psychopathy (pp. 481–494). New York:
Raine, A., Dodge, K., Loeber, R., Gatzke‐Kopp, L., Lynam, D., Reynolds,
C., … Liu, J. (2006). The reactive‐proactive aggression questionnaire:
Differential correlates of reactive and proactive aggression in
adolescent boys. Aggressive Behavior, 32, 159–171.
Rogers, R., Johansen, J., Chang, J., & Salekin, R. T. (1997). Predictors of
adolescent psychopathy: Oppositional and conduct‐disordered symptoms.
Salekin, R. T. (2002). Psychopathy and therapeutic pessimism: Clinical
lore or clinical reality? Clinical Psychology Review, 22, 79–112.
Salekin, R. T., Neumann, C. S., Leistico, A.‐M. R., DiCicco, T. M., &
Duros, R. L. (2004). Psychopathy and comorbidity in a young offender
sample: Taking a closer look at psychopathy’s potential importance
over disruptive behavior disorders. Journal of Abnormal Psychology,
Salekin, R. T., Rogers, R., & Sewell, K. W. (1996). A review and meta‐
analysis of the psychopathy checklist and psychopathy checklist‐
revised: Predictive validity of dangerousness. Clinical Psychology:
Science and Practice, 3, 203–215.
Sevecke, K., Kosson, D. S., & Krischer, M. K. (2009). The relationship
between attention deficit hyperactivity disorder, conduct disorder, and
psychopathy in adolescent male and female detainees. Behavioral
Sciences and the Law, 27, 577–598.
Vitacco, M. J., Neumann, C. S., Caldwell, M. F., Leistico, A.‐M., & Van
Rybroek, G. J. (2006). Testing factor models of the Psychopathy
Checklist: Youth Version and their association with instrumental
aggression. Journal of Personality Assessment, 87, 74–83.
Vitaro, F., & Brendgen, M. (2011). Subtypes of aggressive behaviors:
Etiologies, development and consequences. In T. Bliesnder, A.
Beelman, & M. Stemmler (Eds.), Antisocial behavior and crime:
Contributions of theory and evaluation research to prevention and
intervention. Goettingen, Germany: Hogrefe.
Vitaro, F., Brendgen, M., & Tremblay, R. E. (2002). Reactively
and proactively aggressive children: Antecedent and subsequent
characteristics. Journal of Child Psychology and Psychiatry, 43,
Waschbusch, D. A., Pelham, W. E., Jennings, R., Greiner, J. R., Tarter, R.
E., & Moss, H. B. (2002). Reactive aggression in boys with disruptive
behavior disorders: Behavior, physiology, and affect. Journal of
Abnormal Child Psychology, 30, 641–656.
Waschbusch, D. A., & Willoughby, M. T. (2008). Attention‐deficit/
hyperactivity disorder and callous‐unemotional traits as moderators of
conduct problems when examining impairment and aggression in
elementary school children. Aggressive Behavior, 34, 139–153.
Waschbusch, D. A., Willoughby, M. T., & Pelham, W. E. (1998). Criterion
validity and the utility of reactive and proactive aggression:
Comparisons to attention deficit hyperactivity disorder, oppositional
defiant disorder, conduct disorder, and other measures of functioning.
Journal of Clinical Child Psychology, 27, 396–405.
White, S. F., & Frick, P. J. (2010). Callous‐unemotional traits and their
importance to causal models of severe antisocial behavior in youth. In
R. T. Salekin& D. R. Lynam(Eds.), Handbookof child and adolescent
psychopathy (pp. 135–155). New York: Guilford.
ADHDþODD, Psychopathic Traits, and Aggression11