Research looking precisely at the etiological factors linked with ODD is limited. The literature often examines common risk factors linked with all disruptive behaviors, rather than ODD specifically. Symptoms of ODD are also often believed to be the same as CD, even though the disorders have their own respective set of symptoms. When looking at disruptive behaviors such as ODD, research has shown that the causes of behaviors are multi-factorial. However, disruptive behaviors have been identified as being mostly due either to biological or environmental factors. Genetic influences
Research indicates that parents pass on a tendency for externalizing disorders to their children that may be displayed in multiple ways, such as inattention, hyperactivity, or oppositional and conduct problems. Research has also shown that there is a genetic overlap between ODD and other externalizing disorders. Heritability can vary by age, age of onset, and other factors. Adoption and twin studies indicate that 50% or more of the variance causing antisocial behavior is attributable to heredity for both males and females. ODD also tends to occur in families with a history of ADHD, substance use disorders, or mood disorders, suggesting that a vulnerability to develop ODD may be inherited. A difficult temperament, impulsivity, and a tendency to seek rewards can also increase the risk of developing ODD. New studies into gene variants have also identified possible gene-environment (G x E) interactions, specifically in the development of conduct problems.
High importance must be given to the representation of ODD as a distinct psychiatric disorder independent of conduct disorder.In the context of oppositional defiant disorder and comorbidity with other disorders, researchers often conclude that ODD co-occurs with an attention deficit hyperactivity disorder (ADHD), anxiety disorders, emotional disorders as well as mood disorders. Those mood disorders can be linked to major depression or bipolar disorder. Indirect consequences of ODD can also be related or associated with a later mental disorder. For instance, conduct disorder is often studied in connection with ODD. Strong comorbidity can be observed within those two disorders, but an even higher connection with ADHD in relation to ODD can be seen. For instance, children or adolescents who have ODD with coexisting ADHD will usually be more aggressive and have more of the negative behavioral symptoms of ODD, which can inhibit them from having a successful academic life. This will be reflected in their academic path as students.Other conditions that can be predicted in children or people with ODD are learning disorders in which the person has significant impairments with academics and language disorders, in which problems can be observed related to language production and/or comprehension. See also
Attention deficit hyperactivity disorder (ADHD)
Antisocial personality disorder
Disruptive mood dysregulation disorder (DMDD)
Pathological demand avoidance

References
Further reading
External links
ODD Resource Center – American Academy of Child and Adolescent Psychiatry