Abstract

State-administered correctional institutions in Sweden take care of approximately 600 juvenile delinquents every year. The treatment for these institutionalized young people is based mainly on environmental programs and milieu therapy.

Fifty-six conduct-disordered juvenile delinquents (mean age 17 years) from four institutions were studied with respect to their personality traits, and the prevalence of psychopathy (measured by the Hare Psychopathy Checklist – Revised, PCL-R). One objective was to study the reliability and validity of commonly used personality inventories. In particular, the validity of psychopathy-related personality traits, included in Schalling’s psychopathy model (1978), was examined by studying the relationships between personality traits and psychopathy (PCL-R), the occurrence of previous treatment occasions, and relapse into crime. Four groups, the delinquent participants, a group of high sensation-seekers (air force pilot recruits), normal male adolescent participants, and another group of normal young males, completed a number of personality inventories, which enabled us to obtain measures of personality traits. The personality inventories used were the Karolinska Scales of Personality (KSP), the Eysenck Personality Questionnaire, and the Zuckerman Sensation-Seeking Scales. In addition, the delinquent participants were rated on psychopathy according to the modified version of the PCL-R, designed to be used with young people (Fort, Hart, & Hare, 1990). Both variable-oriented (factor analysis, MANOVA) and person-oriented statistical methods (cluster analysis) were applied.

As expected, most personality traits in the delinquent participants deviated from published norms and from our control groups. The delinquent participants showed a high level of pathology or vulnerability for developing mental disorders (such as substance abuse). About 60% of the delinquent participants had scores above 30 on the PCL-R, and were thus classified as psychopaths according to the manual. Further, 73% had scores between 27 and 40, indicating a high level of psychopathy. Delinquent participants showed a different pattern of sensation-seeking behavior than air force pilot recruits and normal adolescent participants, and differed also in other personality traits. They had a low level of socialization, indicating a lack of ability to take the role of the generalized other, and a tendency to impulsiveness, somatic anxiety and extraversion-sociability. The construct validity (convergent and divergent) of the KSP scales was found to be adequate. Some of the personality traits in delinquent participants, however, showed a different correlation pattern than that found in noncriminal people. Some of the basic scales from the KSP had high reliability, but many were not reliable when used on delinquent participants. Four factors were extracted using the maximum likelihood method. No significant correlations were found between the personality scale scores and the PCL-R scores. Finally, cluster analysis of the reliable and valid psychopathy-related personality scales from the KSP (Impulsiveness, Monotony avoidance, Socialization, Verbal aggression, and Somatic anxiety) identified seven different clusters of delinquent participants.

The uncertain validity of some personality traits (e.g., psychoticism or detachment), the poor reliability of many of the KSP scales (e.g., Guilt, Suspicion, and Inhibition of aggression) when used on this population, together with some minor limitations of the studies (e.g., sample size) are discussed.

In conclusion, the high prevalence of psychopathy in the present sample of male delinquent participants may have important clinical treatment implications, particularly since some researchers have suggested that milieu therapy increases relapse rates into crime in adult psychopaths. Hopefully, appropriate assessment of personality traits and psychopathy (in addition to obvious routine assessments of mental disorders, such as substance abuse or disabilities such as dyslexia), supervision, and the implementation of effective correctional programs, may prevent young people with deviant personalities from aggravating their deviant style of living.

Key words: Personality traits, psychopathy (PCL-R), juvenile delinquents, reliability, validity, assessment.