Other conditions may co-exist with ADHD. A Review by Green et al (1999) reports the following rates of co-morbid conditions with ADHD:
|Oppositional defiant disorder||35%|
However, other studies give different prevalence, particularly for conduct disorder. Many child behavior experts feel that conduct disorder is not an appropriate label for the young child at all.
Realizing the prevalence of other disorders among hyperactive children is extremely important for clinicians who manage children with ADHD. Parents, physicians, and teachers easily tend to focus primarily on the symptoms of disruptive behavior, as do the behavior rating scales commonly used to identify children with ADHD. Unfortunately, these symptoms are not specific enough to confirm a diagnosis of ADHD, as will be demonstrated.