There are no medical tests for diagnosing autism. An accurate diagnosis must be based on observation of the individual’s communication, behavior and developmental levels. However, because many of the behaviors associated with autism are shared by other disorders, various medical tests may be ordered to rule out or identify other possible causes of the symptoms being exhibited. At first glance, some persons with autism may appear to have mental retardation, a behavior disorder, problems with hearing, or even odd and eccentric behavior. To complicate matters further, these conditions can co-occur with autism. However, it is important to distinguish autism from other conditions, since an accurate diagnosis and early identification can provide the basis for building an appropriate and effective educational and treatment program.
A brief observation in a single setting cannot present a true picture of an individual’s abilities and behaviors. Parental (and other caregivers’ and/or teachers’) input and developmental history are important components of making an accurate diagnosis.