You can't! There is is no bright line that separates behavioral characteristics. In addition, there is no test for ODD. The usual standard, as in most psychiatric conditions, is duration and severity. A diagnosis of Oppositional Defiant Disorder is a judgment call and of questionable validity even under the best of circumstances.

Here (http://www.minddisorders.com/Ob-Ps/Oppositional-defiant-disorder.html) is an article that provides a thorough review.

Please be advised that behavior problems in children and adolescents should be diagnosed only following extensive evaluation by mental health specialists with experience in the particular disorder. Psychiatric labeling can have life-long consequences and should be undertaken with extreme caution. Too often that is not the case.

Please review this article and if you have further questions, please ask.