Medical Diagnosis

There are no medical tests for diagnosing autism. An accurate diagnosis must be based on observation of the individual’s communication, social interaction, and the quality of his or her activities and interests. However, because many of the behaviors associated with autism are common to other disorders, some medical tests can be performed in order to rule out other diagnoses or to identify possible causes of the symptoms being exhibited.

Medical professionals who may have experience with autism and other neurodevelopmental disorders include pediatricians (especially developmental pediatricians), neurologists (specifically pediatric neurologists), and child and adolescent psychiatrists. Not every one of these professionals has experience with autism, so parents and caregivers should ask for recommendations of knowledgeable professionals in their area from:

• their local Autism Society affiliate
• autism support groups
• people who have children or other family members with autism
• their state developmental disability centers
• their primary-care provider.

Once a skilled practitioner is identified, the assessment can begin; however, the evaluation itself can vary depending upon the professional administering it, the age of the person being assessed, severity of his or her symptoms, and local available resources. For example, if a very young child (1-3 years old) is showing significant developmental delays, a primary-care practitioner may refer the family to a psychologist, pediatric neurologist or developmental pediatrician for a diagnostic assessment. For guidelines on assessing autism spectrum disorders, click here.

An initial medical assessment typically includes:

• a medical history of the mother’s pregnancy
• review of developmental milestones
• eating and sleeping habits
• coordination
• stomach and bowel functioning
• sensory challenges
• allergies
• medical illnesses, including ear infections, seizures
• any family history of developmental disorders
• any family history of genetic and metabolic disorders
• parents’ and child’s exposure to environmental toxins
• a thorough physical exam
• routine lab tests

While there is no one behavioral or communications test that can detect autism, several screening instruments have been developed that are now being used in diagnosing autism. Individuals with autism often have symptoms of various co-occurring mental, behavioral and physical conditions (see Related Conditions).