Conduct Disorder and ODD

A 9-year-old boy is brought to the child psychiatry clinic by his mother with complaints of persistent disobedience and aggressive behaviour at home and school for the past 18 months. The mother reports that he frequently argues with authority figures, deliberately annoys peers, and has been caught stealing small items from shops twice in the past 6 months. He denies remorse for his actions and blames others for his problems. He has been suspended from school twice for fighting with classmates. His father is an alcoholic and frequently uses physical punishment. On mental status examination, he is irritable, shows poor eye contact, and displays no guilt or anxiety about his behaviour. There is no history of fire-setting, animal cruelty, or serious physical aggression causing injury. What is the most likely diagnosis?

According to DSM-5 criteria, what is the minimum duration of symptoms required for diagnosis of Conduct Disorder?

An 11-year-old girl is referred to the psychiatry clinic after repeated incidents at school: she has been caught stealing money from classmates' bags, lying to teachers about her whereabouts, and deliberately destroying a peer's project to avoid competition. At home, she has physically pushed her younger brother and threatened her mother with a knife during an argument. She has a history of cruelty to animals and has been suspended from school twice. Her parents report she shows no remorse for her actions and blames others. Developmental history is unremarkable. What is the most likely diagnosis?

A 9-year-old boy is brought to the child psychiatry clinic by his mother with a 2-year history of persistent defiance, arguing with teachers and parents, deliberately annoying peers, and frequent angry outbursts. He blames others for his mistakes, is easily angered when corrected, and refuses to follow household rules. His teacher reports he disrupts the class, talks back, and refuses to complete assignments. He denies deliberately hurting animals, destroying property, or violating others' rights. His IQ is normal, and there is no history of ADHD symptoms prior to age 7. What is the most likely diagnosis?

A 13-year-old girl is referred to psychiatry after being caught stealing money from her mother's purse, lying to her parents about her whereabouts, and physically fighting with a classmate who had insulted her. Over the past 18 months, she has been suspended twice for aggressive behavior at school, deliberately damaged school property during an argument with a teacher, and was found shoplifting at a local store. She shows no remorse for her actions and blames others for her problems. Her parents report she has been increasingly defiant since age 10. There is no history of seizures, head trauma, or substance use. What is the most likely diagnosis?