Callous and unemotional traits in children and adolescents living in Great Britain

Few studies have assessed psychopathic traits in community samplesof young people. We investigated the predictive utility ofcallous and unemotional traits in a representative sample of5770 young people from Great Britain. Teachers provided informationon the presence of callous and unemotional traits and parentscompleted the Strengths and Difficulties Questionnaire to determinethe level and impact of psychiatric problems at baseline, 12and 24 months later. Baseline callous and unemotional traitscores independently predicted the number and intensity ofconduct, emotional and hyperactivity symptoms at follow-up.Callous and unemotional traits are longitudinally associatedwith the level and impact of childhood psychiatric problems.

INTRODUCTION

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INTRODUCTION

Over the past decade, interest in childhood psychopathy has grown.^1,2 Although the concept is controversial, if ‘fledgling psychopaths’³ could be successfully identified, thismight represent a breakthrough in the prevention of persistentantisocial behaviour. Frick and colleagues have highlightedthe importance of identifying callous and unemotional traitsas a potential marker for life course persistent antisocial behaviour.^1,4 However, few studies have assessed callous andunemotional traits in community samples and data on their predictiveutility are sparse. We set out to examine the correlates andpredictive utility of callous and unemotional traits in a largeepidemiologically representative sample of young people fromGreat Britain.

Method

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Method

A stratified random sample of 10 496 families was invited toparticipate in the British Child and Adolescent Mental HealthSurvey 2004; a total of 7977 (76%) responded. All study proceduresreceived multicentre research ethics committee approval andinformed consent was obtained from parents. Children in thesurvey were aged 5–16 years. All parents had a face-to-face interview during which they provided socio-demographic detailsand completed the 12-item General Health Questionnaire⁵ and the Strengths and Difficulties Questionnaire (SDQ), a well-validatedmeasure of childhood psychopathology.⁶ Nominated teacherswere mailed a questionnaire (if the family consented). Informedby previous factor analyses^1,4 the teacher questionnaire includedseven statements relating to the presence of callous and unemotionaltraits in the index child:

Makes a good impression at first but people tend to see throughhim/her after they get to know him/her.
Shallow or fast-changingemotions.
Too full of his/her own abilities.
Is usuallygenuinely sorry if s/he has hurt someone or actedbadly.
Canseem cold-blooded or callous.
Keeps promises.
Genuine inhis/her expression of emotions.

The items were all rated on a three-point (0,1,2) Likert scale(not true, partly true, certainly true). Possible total scoreson the scale ranged from 0 to 14, with items 1, 2, 3 and 5being scored 2 for ‘certainly true’ and the remainingitems scored 2 for ‘not true’. A principal componentanalysis showed that the seven items from the scale loaded onto one component, with an eigenvalue of 2.44 (35% of the variance).The scale demonstrated good internal consistency (Cronbach’s ${alpha}$ =0.78).

At 12 and 24 months, parents who had participated in the baselinesurvey and had agreed to be followed up were posted an SDQ.Associations between teacher-rated callous and unemotionaltrait score and 12- and 24-month parent-rated outcomes wereexamined using longitudinal linear regression. Outcomes andcontinuous predictor variables were transformed into z-scores(zero mean and unit standard deviation) so that the magnitudesof regression coefficients could be compared on a common scale.We included appropriate interaction terms in the models inorder to test whether the effects of callous and unemotionaltraits were modified by age or gender. All analyses were performedusing Stata version 8.1 for Windows.

Results

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Results

Callous and unemotional trait score ratings were obtained from5770 teachers (55% of the original sample) and the mean scorewas 1.65 (s.d.=2.25). Callous and unemotional trait score wassignificantly associated with male gender, older age, Blackand minority ethnicity, fair or bad general health, parentalcommon mental disorder, larger family size and lower household income. Outcome data (12- and 24-month) were obtained for 4609young people; an 80% response rate. The following groups wereoverrepresented among those with missing trait ratings or missingoutcome data: older children, those from larger families, thosewith poorer general health, and those from Black and minorityethnic groups.

Table 1 displays the results of longitudinal linear regressionmodels examining adjusted associations between baseline predictorvariables and conduct, hyperactivity and emotional symptomsat 12 and 24 months combined. Callous and unemotional traits,lower household income, the presence of parental common mentaldisorder and the number of SDQ symptoms at baseline were allindependently associated with the three symptom domains atfollow-up. For conduct symptoms, there was weak evidence foran interaction between callous and unemotional traits and gender (P=0.07), with callous and unemotional traits being more strongly associated with conduct symptoms in boys (coefficient=0.09; P<0.001) than in girls (coefficient=0.05; P<0.05). The total SDQ symptom and impact scores at 12 and 24 months werealso independently associated with the baseline callous andunemotional trait symptom score (adjusted coefficient for SDQscore=0.06; P<0.001; adjusted coefficient for impact score=0.05;P<0.001). There was evidence of an interaction between callousand unemotional traits and gender (P=0.03), with callous andunemotional traits being more strongly associated with theSDQ impact score in boys (coefficient=0.07; P<0.001) thanin girls (coefficient=0.03; P=0.08).

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Table 1 Results of longitudinal linear regression models showing the effect of baseline predictor variables on conduct, hyperactivity and emotional symptoms at 12 and 24 months (n=4609 for all models)

Discussion

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Discussion

In this study we have provided preliminary evidence to showthat the presence of callous and unemotional traits is longitudinallyassociated with the level and impact of childhood psychopathologyand that this is independent of the effects of establishedrisk factors for childhood psychiatric illness. The strongestpredictor of psychiatric symptoms at follow-up was the total baseline symptom score, and in comparison, the predictive valueof callous and unemotional traits and socio-demographic factorswas small. Nevertheless, few studies have assessed the predictiveutility of callous and unemotional traits in community samplesof young people^7,8 and to the best of our knowledge, the presentstudy is the largest to date. The presence of callous and unemotionaltraits in young people, particularly in boys, seems to confera vulnerability to additional mental health problems and thisfinding has both clinical and research implications. From aclinical perspective, screening for the presence of callousand unemotional traits may assist health professionals to identifya particularly vulnerable group of young people. From a researchperspective, adding questions on personality traits to childhoodpsychiatric questionnaires may increase their predictive value.

Strengths of the study include the use of a large representativesample of young people and the fact that we obtained informationfrom two sources, parents and teachers, permitting us to minimiserater bias. However, despite the fact that the callous andunemotional trait scale demonstrated factorial unity and goodinternal consistency, further research is required to establish its detailed psychometric properties. In addition, higher callousand unemotional trait scores were associated with groups ofchildren overrepresented in the missing data group. Our analyseswere therefore conducted on a ‘healthier than normal’population and the findings require replication.

REFERENCES

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