How is Autism Diagnosed?
There are no medical tests for diagnosing autism. An accurate diagnosis is best obtained through a collaborative approach by several professionals who are competent and familiar with autism. It is also wise to rule out medical conditions that often have symptoms that may appear to be autism. A medical doctor may evaluate the child to ensure that there are no medical disorders present.
Because the characteristics of pervasive developmental disorders can vary so widely among children, it is extremely important to consult with specialists. Practitioners that have limited training or exposure to autism are more likely to misdiagnose the child, which may result in the loss of valuable treatment time.
Specialists to consider consulting include:
developmental psychologists, developmental pediatricians, pediatric neurologists, speech and language therapists, occupational therapists, or other professionals knowledgeable about autism. In addition to direct observation, diagnosticians often use the following assessment tools:
- Autism Diagnostic Observation Scale (ADOS)
- Autism Diagnostic Interview (ADI)
- Checklist for Autism in Toddlers (CHAT)
- Childhood Autism Rating Scale (CARS)
- Gilliam Autism Rating Scale, 3rd Ed. (GARS-3)
- Wechsler Scale for Children, 3rd edition (WISC-III)
- Woodcock Johnson, 3rd edition (WJ-III)
- Vineland Adaptive Behavior Scales
A brief observation in a single setting cannot present a true picture of a child’s abilities and behaviors. At first glance, the child with autism may appear to have mental retardation, a different behavioral disorder, or even problems hearing. Because diagnosis and assessment results guide the development of a treatment approach, it is essential that diagnosticians conduct a thorough evaluation of the child, using information from many different sources (different raters, variety of environmental contexts).