To determine whether a child has oppositional defiant disorder, a mental health provider can do a comprehensive psychological evaluation including assessing overall health; frequency and intensity of the child’s behaviors; the behavior across multiple settings and relationships; the presence of other mental health, learning, or communication disorders; and related mental health issues.

Because ODD often occurs along with other behavioral or mental health problems, symptoms of ODD may be difficult to distinguish from those related to other problems.

Children with ODD are often in an angry and irritable mood and lose their temper, are touchy or easily annoyed by others, angry and resentful, and display argumentative and defiant behavior. They argue with adults or people in authority, actively defy or refuse to comply with adults, deliberately annoy people, and blame others for their mistakes or misbehavior. They can often be spiteful or vindictive. These behaviors are displayed more often than is typical for their peers; for children younger than 5 years, the behavior occurs on most days for a period of at least six months. For children 5 years or older, it occurs at least once a week for at least six months.