Diagnosis: What to Expect

With the documented benefits of early intervention for learners with autism, the earlier the diagnosis can be made, the better. As there is no genetic or medical test for autism, clinicians rely on behavioral observation, generally quantified through the use of a standardized diagnostic scale, to arrive at the diagnosis. In general, diagnosis is a two step process: 1) screening, and 2) a comprehensive diagnostic evaluation.

It’s important for a child with autism to be diagnosed as early as possible. “Wait and see” is not be the best approach. If you’ve expressed concerns about your child’s development and your pediatrician suggests you wait to see how your child progresses, carefully consider pursuing further evaluation. Studies have shown that the earlier a child is diagnosed, the sooner a treatment program can be started, and the better the results for the child in the long term. Children should be screened for a developmental disorder by their Primary Care physician during every "well visit".

If you or your doctor thinks your child may have autism, you should take him or her to a developmental specialist for a thorough evaluation. This is the first step in ruling out any other problems or conditions and helping get your child started on the right treatment. Examples of specialists are neurologists, child psychologists, psychiatrists, developmental pediatricians, or speech therapists.

A health care professional will make a diagnosis of autism based on an evaluation of your child’s behavior, communication abilities, and developmental progress. There are currently no medical or laboratory tests to detect autism, and no physical signs known to date. However, there are specific tests given to rule out other abnormalities, and several forms of assessment to definitively point to a diagnosis of autism and its degree of severity.

A diagnosis of autism is usually made when children are between two and three years of age, when parents may begin noticing delays in verbal and non-verbal communication and social interaction.

There are several tests that are used to screen or diagnose autism. These include:

  • The Autism Diagnostic Interview - Revised (ADI-R): is a semi-structured interview with the child's parents used by a trained specialist to help make a definitive diagnosis.
  • The Autism Diagnostic Observation Schedule - Generic (ADOS-G): is a structured interview with directed activities also used by a trained specialist to help make a definitive diagnosis.
  • CARS rating system (Childhood Autism Rating Scale) observes a child’s behavior and uses a 15-point scale to evaluate a child’s relationship to people, body use, adaptation to change, listening response, and verbal communication.

Rating scales are particularly useful to track your child’s more significant changes over time. For more information on these and other assessments commonly conducted by autism professionals in consultation with parents, see OAR’s Life Journey through Autism: A Parent’s Guide to Assessment.

If your child is diagnosed with autism, your ability to cope and navigate the road ahead will provide challenges, along with moments of hope and accomplishment. To find resources that can help you adjust to this difficult diagnosis and take some very helpful first steps, please see our Search for Resources page.