When a child does not pass an autism screening, or any time a parent expresses concerns about autism, the next step should be referral for a formal evaluation to confirm or rule out autism. Diagnosing autism, however, can be a complex process that might involve professionals from several specialties, including developmental pediatricians, therapists, neurologists, psychiatrists, or psychologists.
Although most of these professionals can technically make a diagnosis on their own, a multidisciplinary approach is the ideal way to arrive at a diagnosis. A team approach allows a variety of professionals to interact with a child and evaluate multiple factors that are associated with autism. The team of specialists usually includes:
- A developmental pediatrician, neurologist, and/or psychiatrist conduct medical tests and exams
- A psychologist conducts behavioral assessments and evaluates cognitive functioning
- A speech-language pathologist assesses receptive and expressive language and social communication skills
- An occupational therapist assesses fine motor skills, sensory challenges, and child’s interactions with his or her environment
There is no specific medical test, such as a blood test or brain scan, which can diagnose autism. Instead, doctors conduct the following exams and tests to rule out other diagnoses and identify related medical conditions:
- Complete health history of child and family
- Thorough physical exam and in some cases a neurologic exam
- Hearing test
- In some cases, blood test to check for elevated lead levels as well as genetic or metabolic abnormalities
- In some cases, electroencephalogram (EEG)
Behavioral assessments should include:
- History of developmental milestones and behavior
- Testing that looks at overall developmental status and/or intelligence in comparison to social skills
- A standardized assessment tool that is specific to autism spectrum disorder. Such tools are often in the form of questionnaires and rely on parent input. Parents have an important part in helping to make an accurate diagnosis.
- Direct clinical observation of child in various situations
All of these findings, coupled with the results from speech-language and occupational therapists’ evaluations, are used to compile a profile of the child’s behavior. If this profile fits the criteria for autism as defined in the DSM-5, a diagnosis of autism is given.
Accurate and timely diagnosis of autism is vital to ensure access to early intervention services and hopefully achieve positive results.
Reviewed by Dr. Sara Connolly, January 2019
- Any time a child fails a screening or a parent has concerns about autism, steps should be taken to rule out or diagnose autism.
- A team of multi-disciplinary health professionals best diagnoses autism.
- An autism diagnosis is typically given after the child has been assessed for a variety of factors, including development and behaviors.
- It’s best to diagnose autism as early as possible to help ensure early intervention.