Diagnostic criteria (high level)

CD involves behaviours such as aggression to people/animals, destruction of property, deceitfulness or theft, and serious violations of rules. Symptoms must persist for at least 12 months (with at least one criterion in the past 6 months) and cause significant impairment.

Specifiers & subtypes

• Child‑onset type: onset of at least one symptom before age 10 — associated with worse prognosis.
• Adolescent‑onset type: onset after age 10 — generally better prognosis than child‑onset.
• With limited prosocial emotions (callous‑unemotional traits): lack of remorse, shallow affect, unconcern about performance — predicts persistent antisocial behaviour.

Common presentations & red flags

• Physical fights, bullying, cruelty to animals, use of weapons.
• Deliberate property destruction (arson, vandalism), shoplifting, lying and truancy.
• Running away from home, staying out late, association with delinquent peers.
• Red flags: weapon access, sexual offending, serious violence, escalating criminal charges, substance dependence.

Assessment checklist

1. Obtain developmental and family history, review for conduct symptoms before age 10 (to identify child‑onset).
2. Gather collateral: school records, police/juvenile records, caregiver and teacher reports.
3. Screen for comorbid ADHD, learning difficulties, ASD, mood disorders, PTSD and substance use.
4. Assess for trauma, abuse or neglect which may underlie behaviours; evaluate safety and legal risks.
5. Use structured instruments where available (e.g., the Child Behavior Checklist, the Antisocial Process Screening Device, Structured diagnostic interviews).

Treatment — evidence‑based approaches

Family‑based interventions

• Parent Management Training (PMT) / Parent–Child Interaction Therapy (PCIT): teach caregivers consistent, positive behaviour management and contingency strategies.
• Multisystemic Therapy (MST): intensive home‑ and community‑based programme for severe or chronic cases with strong evidence for reducing reoffending.

School & community interventions

• School‑based behaviour plans, mentoring, vocational support and structured after‑school programmes to reduce peer influences and increase prosocial engagement.

Individual therapies

• Cognitive‑behavioural strategies for anger management, problem‑solving and social skills training.
• Trauma‑focused therapies where PTSD or abuse history present.

Pharmacotherapy

• No medication treats CD per se; medications target comorbid conditions (stimulants for ADHD, SSRIs for mood/anxiety) or severe aggression (atypical antipsychotics) short‑term under specialist guidance.

Risk management & legal liaison

• Safety planning for victims, restrict weapon access, and coordinate with child protection and juvenile justice systems when required.
• Document risks, interventions, and engage multidisciplinary teams (social work, education, probation) to create coordinated plans.
• Consider secure or residential interventions for those with persistent dangerous behaviours despite community care.

Key takeaways

• Early identification and family‑based interventions (PMT, PCIT, MST) are central to improving outcomes in CD.
• Assess for comorbidity and trauma; coordinate care across health, education and justice sectors.
• Prioritise safety, legal liaison and long‑term psychosocial supports to reduce harm and promote rehabilitation.