Conduct Disorder

Conduct disorder (CD) is a mental health condition of childhood and adolescence in which a young person shows a repetitive and persistent pattern of behavior that violates the basic rights of others or major age-appropriate social rules. It goes beyond ordinary misbehavior or defiance, involving behaviors such as aggression toward people or animals, destruction of property, deceit or theft, and serious rule violations like running away from home. Unlike oppositional defiant disorder, which centers on argumentativeness and defiance, CD involves more serious harm to others.

Conduct disorder matters because it affects the young person, their family, school and community, and because it is linked to later difficulties, including adult antisocial personality disorder in a substantial minority of cases. It is also more treatable than many people assume, especially with early, family-centered help.

DSM-5 Diagnostic Criteria

The DSM-5-TR (ICD-10-CM codes F91.1, F91.2 and F91.9) requires a repetitive and persistent pattern shown by at least three of the following 15 behaviors in the past 12 months, from any category, with at least one present in the past 6 months:

Aggression to People and Animals

• Often bullies, threatens or intimidates others.
• Often starts physical fights.
• Has used a weapon that can cause serious physical harm.
• Has been physically cruel to people.
• Has been physically cruel to animals.
• Has stolen while confronting a victim, such as mugging.
• Has forced someone into sexual activity.

Destruction of Property

• Has deliberately set fires with the intention of causing serious damage.
• Has deliberately destroyed others' property.

Deceitfulness or Theft

• Has broken into someone else's house, building or car.
• Often lies to obtain goods or favors or to avoid obligations ("cons" others).
• Has stolen items of nontrivial value without confronting a victim, such as shoplifting.

Serious Violations of Rules

• Often stays out at night despite parental prohibitions, beginning before age 13.
• Has run away from home overnight at least twice, or once for a lengthy period.
• Is often truant from school, beginning before age 13.

The behavior must cause clinically significant impairment in social, academic or occupational functioning. If the person is 18 or older, criteria for antisocial personality disorder must not be met. Clinicians also rate current severity as mild, moderate or severe.

The criteria describe behavior, not character. A careful assessment considers the context: for example, a teenager who runs away from an abusive home or truants to escape bullying may not have conduct disorder at all. Diagnosis should only be made by a qualified professional after gathering information from several sources, such as parents, teachers and the young person.

Childhood-Onset vs. Adolescent-Onset

The DSM-5-TR specifies onset type because it predicts the course. This distinction is closely tied to psychologist Terrie Moffitt's developmental theory of "life-course-persistent" versus "adolescence-limited" antisocial behavior.

An "unspecified onset" type is used when there is not enough information to tell. Moffitt's later follow-ups of the Dunedin cohort showed that even "adolescence-limited" young people sometimes had lingering difficulties in their twenties, so the distinction is a tendency rather than a guarantee.

Callous-Unemotional Traits

The DSM-5 introduced the specifier "with limited prosocial emotions" to capture what researchers call callous-unemotional (CU) traits. It applies when a young person persistently shows at least two of the following over 12 months, across relationships and settings:

• Lack of remorse or guilt.
• Callousness, or lack of empathy.
• Unconcern about performance at school, work or other important activities.
• Shallow or deficient emotional expression.

Research led by Paul Frick and others shows that young people with CU traits tend to have more severe, more planned aggression, and more persistent problems. Their difficulties appear more strongly influenced by genetics and less linked to anxiety. CU traits are associated with later psychopathic traits, though they are not the same thing, and they are not fixed: warm, responsive parenting has been linked to reductions in CU traits over time, and treatments that emphasize rewards and positive relationships appear more effective for this group than punishment.

Causes

Conduct disorder arises from interacting biological, psychological and social influences.

Biological and temperamental factors

• Genetics: twin studies suggest roughly half of the variation in antisocial behavior in young people is linked to genetic factors, with higher heritability when CU traits are present.
• Temperament: difficult temperament, poor self-control and fearlessness in early childhood are associated with later conduct problems.
• Neurodevelopment: ADHD, language difficulties and lower verbal ability are more common in childhood-onset CD.
• Brain function: research reports, on average, reduced amygdala reactivity to others' distress in youth with CU traits and heightened threat reactivity in others with reactive aggression.
• Prenatal factors: exposure to tobacco, alcohol and other substances in pregnancy and birth complications are associated with higher risk.

Family and social factors

• Parenting: harsh, inconsistent or uninvolved discipline. Gerald Patterson's research described a "coercive cycle" in which parent and child escalate conflict until one gives in, unintentionally rewarding difficult behavior.
• Adversity: child maltreatment, neglect and exposure to family violence. See childhood trauma.
• Family stress: parental mental health or substance use problems, and parental antisocial behavior.
• Community: poverty, neighborhood violence and limited opportunities.
• Peers: rejection by prosocial peers in childhood and association with antisocial peers in adolescence.

Influences run in both directions. A child's challenging behavior can make parenting more stressful and harsher, which can worsen behavior further. Breaking this cycle is a central aim of treatment.

Related and Co-occurring Conditions

Conduct disorder often co-occurs with ADHD, learning difficulties, depression, anxiety and substance use. Clinicians also distinguish it from:

• Oppositional defiant disorder: defiance and irritability without serious violations of others' rights.
• ADHD alone: impulsive behavior that is not primarily rule-violating.
• Mood disorders: irritability and aggression that occur mainly during mood episodes, as in disruptive mood dysregulation disorder or bipolar disorder.
• Intermittent explosive disorder: impulsive aggressive outbursts without the broader pattern of CD.
• Adjustment disorder with disturbance of conduct: behavior problems that begin in response to a specific stressor.

Treatment

Treatment works best when it is started early, involves the family, and addresses the settings where the young person lives, learns and spends time. Guidelines such as the UK's NICE guideline on antisocial behavior and conduct disorders recommend parent and family programs as the core of treatment.

Parent Management Training

For younger children, parent management training is the best-supported approach. Programs such as the Incredible Years, Parent-Child Interaction Therapy (PCIT) and Triple P teach parents to use praise and rewards for positive behavior, give clear instructions, apply calm and consistent consequences, and spend positive time with their child. Many trials show reductions in conduct problems. Our guides to parenting strategies and parenting styles explain the principles behind them.

Multisystemic Therapy (MST)

Developed by Scott Henggeler and colleagues, MST is an intensive home- and community-based treatment for adolescents with serious antisocial behavior. Therapists work with the family, school, peers and community, often for several months. Many trials have found reductions in re-arrest and out-of-home placements, though results have been more mixed in some replications outside the US.

Functional Family Therapy (FFT)

FFT is a shorter, family-based intervention that targets communication and relationship patterns that maintain problem behavior. It has a strong evidence base for reducing reoffending among adolescents.

Cognitive-Behavioral Approaches

Individual or carefully structured group programs teach problem-solving, anger management and social skills. Alan Kazdin's problem-solving skills training, often combined with parent training, has shown benefits for children with conduct problems. See anger management for related skills.

Treat Comorbidities

Addressing co-occurring ADHD, learning difficulties, depression, trauma or substance use can substantially reduce conduct problems. School support, including help with academic skills and positive behavior approaches, is often part of the plan.

Medication

No medication treats conduct disorder itself, and guidelines do not recommend routine medication for it. A doctor may discuss medication for co-occurring conditions such as ADHD, and occasionally, under specialist supervision, for severe aggression that has not responded to other approaches.

What to Avoid

• "Scared Straight" programs: a Cochrane review by Anthony Petrosino and colleagues found these prison-visit programs increased later offending compared with no intervention.
• Boot camps and purely punitive approaches: research shows little benefit and possible harm.
• Groups made up only of antisocial youth: Thomas Dishion and colleagues found that such groups can lead to "deviancy training," in which young people reinforce each other's problem behavior.

Prevention and Outlook

Early support for families, high-quality early education, home visiting programs for at-risk parents, and school-based social-emotional learning programs have all been linked to fewer conduct problems later on. Outcomes are better when problems are identified early, when families are engaged, and when co-occurring conditions are treated. Many young people with conduct disorder go on to lead stable, productive adult lives, particularly with consistent support.

Parents and caregivers concerned about a child's behavior can start with the child's doctor, school psychologist or a licensed child therapist. Our overview of behavioral problems in childhood describes what is typical at different ages.

Conclusion

Conduct disorder is among the most consequential childhood mental health conditions, with effects that reach families, schools and the justice system. It is also more treatable than commonly believed, especially when intervention happens early and addresses the many influences shaping a young person's behavior. Parent training, multisystemic therapy and functional family therapy have changed outcomes for many young people who might otherwise have followed a path toward adult antisocial behavior, while punitive approaches have proved ineffective or harmful.