title: Evaluation of the known behavioral heterogeneity in conduct disorder to improve its assessment and treatment.
abstract: BACKGROUND
  Conduct Disorder (CD) is among the most highly represented diagnostic problems in child and adolescent mental health treatment settings. There is a great deal of heterogeneity within the CD category, with potentially important implications for case conceptualization and treatment. The current review sought to detail forms of heterogeneity within CD, including callous-unemotional traits, comorbid Attention-Deficit Hyperactivity Disorder (ADHD), aggressive and nonaggressive antisocial behavior, and age of onset.
  
  
  METHODS
  The current review summarizes research on etiological factors, correlates, and trajectories associated with distinguishable dimensions of CD, and considers how this heterogeneity should be incorporated into the assessment and treatment of CD.
  
  
  RESULTS
  Callous-unemotional traits have been associated with a more severe and persistent form of CD, as have comorbid ADHD and child-onset CD. Aggressive antisocial behavior is a stable behavioral dimension that emerges in early childhood and is associated with high levels of neuroticism. Nonaggressive antisocial behavior demonstrates specific associations with impulsivity, is most frequent during adolescence, and evidences more moderate levels of stability.
  
  
  CONCLUSIONS
  Conduct disorder is a highly heterogeneous disorder. Although the clinical implications of this heterogeneity are discussed, future research is clearly needed to shore up our understanding of the clinical ramifications of the sub-dimensions within CD.
authors.affiliation: Department of Psychology, Michigan State University, East Lansing, MI, USA.
authors.forename: Ashlea M
authors.initials: AM
authors.lastname: Klahr
authors.forename: S Alexandra
authors.initials: SA
authors.lastname: Burt
mesh_terms: D000293:Adolescent; D002648:Child; D019955:Conduct Disorder / Q000145:classification* / Q000175:diagnosis / Q000503:physiopathology* / Q000628:therapy; D006801:Humans
keywords: Aggression; antisocial behavior; callous-unemotional traits; conduct disorder; nonaggressive rule-breaking