From: Chapter 8, "Diagnosis," in Acting Out (© 2007)
Conduct disorder (CD) may be diagnosed in a child or adolescent who has repeatedly and consistently shown a number of severely aggressive and anti-social behaviours. Young people with CD find it very difficult to follow rules and behave in socially acceptable ways. They are often viewed by parents, teachers, social service providers, other adults and their peers as "bad" rather than as having a mental health problem.
Many factors may contribute to a young person developing CD, including brain damage, genetic makeup, failure at school and traumatic life experiences, such as abuse. Young people with CD may also have other mental health disorders.
The DSM makes a distinction between young people who display at least one symptom of the disorder before the age of 10 and those who first display symptoms of the disorder after the age of 10. Those in the former group are more likely than those in the latter group to continue to display severely aggressive, anti-social and illegal behaviour over time. They are also more likely to be boys, whereas young people in the latter group are as likely to be girls as boys.
Studies have shown different rates of CD among young people, varying from one per cent to nine per cent.
Symptoms of CD
Young people may be diagnosed with conduct disorder if they have displayed three or more of the following symptoms in the past 12 months, with at least one symptom also present in the past six months:
Aggression towards people and animals
- frequently bullies, threatens or intimidates others
- often initiates physical fights
- has used a weapon that could cause serious physical harm to others (for example, a bat, brick, broken bottle, knife or gun)
- has been physically cruel to people
- has been physically cruel to animals
- has stolen from victims while confronting them (for example, during an assault)
- has forced someone into sexual activity
Destruction of property
- has deliberately engaged in fire setting with the intention of causing damage
- has deliberately destroyed others' property
Deceitfulness or stealing
- has broken into someone else's building, house or car
- often lies to obtain goods or favours, or to avoid obligations
- has stolen valuable items without confronting a victim (for example, shoplifting, but without breaking and entering)
Serious violations of rules
- often stays out at night despite parental objections (starting before age 13)
- has run away from home overnight at least twice
- is often truant from school (starting before age 13)*
Studies indicate that the most effective way to manage CD among young people is through the use of a varied approach that involves a wide range of programs, including training in social skills, problem-solving skills, anger management and (for the parents) parent management skills training. Providing such treatment often requires co-ordination among people working in various systems: the education system, the mental health system, the child welfare system and, in the case of a young person in trouble with the law, the juvenile justice system. Young people with conduct disorder can, however, be difficult to engage in treatment programs for various reasons. They may, for example, have poor verbal skills or low intelligence. The earlier and younger a child with conduct disorder receives treatment, the more likely it is that the treatment will show benefits.
* Adapted with permission from the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision. Copyright 2000, American Psychiatric Association.
Addressing "normal" aggression
Working with young people who have mental health problems that may include aggressive behaviour
- Disruptive behaviour disorders