Diagnosis of Conduct Disorder Psychiatric assessment Diagnostic and Statistical Manual of Mental Disorders, Fifth edition (DSM-5-TR) criteria Conduct disorder is diagnosed in children or adolescents who have demonstrated ≥ 3 of the following behaviors in the previous 12 months plus at least 1 in the previous 6 months: Aggression toward people and animals Destruction of property Deceitfulness, lying, or stealing Serious violations of parental rules Symptoms or behaviors must be significant enough to impair functioning in relationships, at school, or at work.