conduct disorder

Conduct Disorder is one of the most common psychiatric disorders in children and adolescents between the ages of four and sixteen. It is distinguished by a persistent pattern of behaviour in which the basic rights of others and major age-appropriate societal norms are violated. Children with this disorder have great difficulty following rules and behaving in a socially acceptable way. They are often viewed by other children, teachers, and parents as "bad" or delinquent, rather than mentally ill. They are "troublesome" children, more often than "troubled" children.

Major symptoms of conduct disorders include:

  • expression of anger
  • verbal and physical aggression with other children, adults and animals
  • destruction of property
  • deceitfulness or theft
  • serious violation of rules

Developmental Considerations:

These disturbances in behaviour cause clinically significant impairment in social, academic or occupational functioning. Conduct disorder frequently co-exists with other psychiatric disorders, including depression, oppositional defiant disorder, or attention-deficit/hyperactivity disorder. In fact, a typical progression seen as children develop is:

  • 0 - 4 years irritable, difficult child
  • 4 - 8 years ADHD
  • 8 -12 years oppositional defiant disorder
  • 12-16 years conduct disorder
  • Adult Antisocial Personality Disorder

One developmental model of the disorder shows the following progression: Noncompliance in pre-school, which leads to a coercive parent/child relationship. This then leads to rejection by peers and teachers, coercive peer and teacher relationships, association with delinquent peers and poor school performance. Ultimately this leads to delinquent and antisocial behaviours.

Early Onset Conduct Disorder (classified as before age 8 or 9)

  • starting as early as age 3, 4, 5 or 6
  • characteristics include cognitive/language deficits, comorbid ADHD, extreme aggressiveness, reading difficulties
  • inside factors include poor performance on neuro-psychological tests, difficult temperaments as babies
  • outside factors include poor parenting
  • prognosis for children with early onset Conduct Disorder is poor

Late Onset Conduct Disorder

  • despite similarity of characteristics in adolescence, these children have a different childhood history
  • in earlier childhood, these children are less violent, show leadership qualities, show desired intimate relationships, are more attached to their families, have less pathological personality profiles
  • usually, these children have some significant change in their lives which leads to the onset of these behaviours
  • prognosis for children with late onset Conduct Disorder is more positive than for those with early onset Conduct Disorder


As with any clinical diagnosis, a broad-based, behavioral evaluation is necessary in order to rule out other diagnostic categories with overlapping symptoms, and to confirm the actual diagnosis. An approach, such as the decision tree method from DSM, structured clinical interviews, etc., which allow the practitioner to eliminate other diagnoses and confirm the actual diagnosis, is recommended.

Nonetheless, the following steps are necessary in the evaluation of a child, which could lead to a diagnosis of Oppositional Defiant Disorder or Conduct Disorder:

  1. interview with the parents or a parent, to obtain information about the child's early development, and symptoms, and present symptoms. Current and past stresses in the family that could impact on the child must be probed
  2. parent interview to determine the behaviour management techniques that have been tried, and their outcomes, and how acceptable the child's present behaviour is to the parents
  3. medical history, obtained from the parent, must consider the impact of medical problems that could contribute to behaviour problems
  4. a review of the OSR, seeking information on behavioral symptoms reported since school entry
  5. intellectual screening to establish the child's developmental functioning level, against which to compare behavioral functioning. Defiant and oppositional behaviour patterns which relate more to developmental differences, as may be seen in children with IQs at the extreme ends of the scale, must be ruled out
  6. a complete learning disabilities assessment to determine whether learning disabilities are also evident
  7. the history of the behaviour pattern must be established to demonstrate a gradual onset of symptoms, rather than an acute onset which could reflect stresses in the family
  8. the teacher and parents must complete a questionnaire which identifies the student's behaviours and their frequency, to show the settings in which the behaviours are most apparent
  9. psychometric measures, clinical judgement and qualitative information must be considered in coming to the diagnosis
  10. consider a wide range of childhood disorders that could account for the behavioral symptoms, before making any diagnosis
  11. consider oppositional defiant disorder and conduct disorder together before completing the diagnosis, especially for an older child

Suggested Assessment Techniques

  • Behavior Checklists:
  • Behaviour Assessment System for Children
  • Social Skills Rating Scale
  • Scales of Independent Behaviour-Revised
  • Connors Rating Scales-Revised
  • Interviews based on diagnostic criteria
  • Self reports, Peer reports, Reports of significant others


General considerations:

  • use behavioral criteria to determine improvement
  • individual psychotherapy is not successful except with children and adolescents who realize that their behaviour causes problems for themselves, and have a desire to change
  • group therapy appears not to be effective in most studies
  • most family therapies are not effective
  • while some programmes give initial improvements, not all lead to lasting change and prevent recidivism

Treating Early Onset Conduct Disorder

  • where antisocial behaviour first appeared before the age of six and persistent, Conduct Disorder should be seen as a lifelong disability, which requires lifelong support, and is not amenable to the medical model of treatment and cure
  • treat with long-term follow-up and readiness to intervene whenever necessary
  • provide lifelong supports so the adolescent can learn to live with Conduct Disorder, without developing major symptomatology
  • aggression for these children is a stable personalty trait
  • get a cognitive, neurological and psychiatric assessment
  • programme for their cognitive and neurological deficits and personality traits
  • tailor treatment to suit the youth and family

Treatments that reduce the rate of recidivism

  • Multi-systemic therapy: family, school, peers and neighbourhood
  • Problem solving training
  • Getting and keeping a job
  • Behavioral Systemic Family Therapy
  • Continuity from child/adolescent services to adult services

Psychological Services of the Toronto District School Board has developed a Psychological Assessment Checklist (.pdf) for Oppositional Defiant Disorder and Conduct Disorder outlining best practice for the assessment and diagnosis of these conditions.

For an excellent review of the literature on diagnosis and intervention for conduct disorder, see the May 2001 publication Evidence Based Practices for the Treatment of Conduct Disorder in Children and Adolescents available at the website for Children's Mental Health Ontario.