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What is Autism Testing?

Autism is most often tested in children but can also be diagnosed in teens and adults. Diagnosing someone with autism as early as possible allows them to get the services and support they need to reach their full potential. Diagnosing autism (also commonly referred to as autism spectrum disorder, ASD or being on the spectrum) can be challenging because there is no medical test (or lab tests) to diagnose the disorder. Instead, doctors must look at the child’s developmental history and behavior in order to make an autism diagnosis. To figure out if a child has autism they are observed and evaluated on their development in several key areas:

  • Language & Communication
  • Social Awareness & Interaction
  • Restricted Interests & Repetitive Behavior

Autism Can Sometimes be Detected at 18 Months of Age or Younger

By age 2, early signs of autism can be diagnosed by an experienced professional. However, many children do not receive a final diagnosis until much older. Some people are not diagnosed until they are adolescents or even adults.

How Autism Tests for Children Are Conducted

Because autism is a developmental disability, the evaluation will usually include tests of language, intelligence, behavior and adaptive behavior such as daily living skills and activities. Some information is gathered through tests given directly to the child, and others are captured on forms completed by parents, teachers, or caregivers.

Autism tests vary depending on the age of the child being assessed, the severity of their needs, and the professional administering the test. An assessment for autism will typically include:

  • A medical history of the mother’s pregnancy
  • A measurement of developmental milestones
  • Identifying sensory challenges
  • Medical illnesses, including ear infections and seizures
  • Any family history of developmental disorders
  • Any family history of genetic and metabolic disorders
  • An assessment of cognitive functioning
  • An assessment of language skills
  • An autism-specific observational test and interview

Types of Autism Tests

While there are no lab tests, there are a number of different screening tests administered to detect autism. It is important to use a test that researchers and health professionals trust to identify this condition.

The Autism Diagnostic Observation Schedule, Second Edition (ADOS®-2) is considered by many to be the “gold standard” for autism assessments. There are also several other commonly used tests:

  • Ages and Stages Questionnaire (ASQ)
  • The Modified Checklist for Autism in Toddlers (M-CHAT).
  • Autism Diagnostic Interview–Revised (ADI®-R)
  • Childhood Autism Rating Scale, Second Edition (CARS™2)
  • Monteiro Interview Guidelines for Diagnosing the Autism Spectrum, Second Edition (MIGDAS™-2)
  • Social Communication Questionnaire
  • Social Responsiveness Scale
  • Gilliam Autism Rating Scale, Third Edition (GARS-3)
  • Tele-ASD-Peds (for telehealth assessments)

How Autism Symptoms in Children Are Evaluated

Autism symptoms are evaluated through two components: parent/caregiver interviews and direct observation.

Parents/caregiver interviews gather information about their child’s development from birth to the time of evaluation, explore pregnancy and birth history, health history, school history, behavioral and emotional health, and other details that may affect the child’s behavior or development.

Direct observation is used to determine if the symptoms reported in the interview are visible.
In many cases parent/caregiver interviews and direct observation are enough to evaluate a child for autism. In some situations it may be helpful to also interview the child’s teacher or other adults who know the child well. The goal is to have enough information about the child to understand how they function in different environments.

The person conducting the evaluation compiles all of this information and applies their training and experience to determine the diagnosis. They objectively consider other possible diagnostic explanations or conditions that may happen along with, or in place of, autism, while ultimately looking to answer the question “Does this child have autism?”

Autism Tests for Teens

Autism screening for teens are looking for similar indicators that are used for children. They will interview teenagers and their parents or caregivers, review their developmental history, see how they have developed, and watch how they interact with others.

Autism Tests for Adults

An adult evaluation reviews your developmental, medical and psychological history, and cognitive functioning. An important part of the evaluation is the participation of someone such as a parent, care-provider, sibling, or relative who can report on your early developmental history. This information can be more difficult to obtain for adults, but it can help speed the process up.

Many adults report that finding someone to diagnose them with autism can be difficult.
Some professionals feel less qualified to diagnose adults, as autism may present itself differently, or it may be complicated by the person’s life history and co-occurring mental health conditions. A good place to start to find someone who is qualified to render a diagnosis is to speak to your primary care physician.

Find Autism Testing Providers

Getting Evaluated under the Individuals with Disabilities Education Act
There are two ways a child can be evaluated under the Individuals with Disabilities Education Act:

  1. At the Request of a Parent or Guardian

A parent or guardian can request an evaluation by calling or writing the director of special education or the principal of the child’s school. If the child attends a private or parochial school, the parent may need to contact the local public school district for this evaluation. It is important to place an evaluation request in writing and the parents should keep a copy to help track timing of the process.

  1. At the Request of a School

An evaluation to consider educational autism can be completed as part of an initial evaluation, or through the process of re-evaluation. For students who already receive special education services, a re-evaluation must take place at least every three years. It may however be conducted more often if the parent or a teacher makes a written request. An evaluation may also focus on a specific area of concern.

What Causes Autism?

There is no single cause of autism. Research suggests that autism develops from a combination of genetic and nongenetic or environmental influences. It is important to keep in mind that an increased risk does not mean that someone will have autism. For example, some gene changes associated with autism can also be found in people who don’t have the disorder. Similarly, most people exposed to an environmental risk factor for autism will not develop the disorder.

Autism’s Genetic Risk Factors

Autism does tend to run in families. Changes in certain genes increase the risk that a child will develop autism. If a parent carries one or more of these gene changes, they may get passed to a child (even if the parent does not have autism). Other times, these genetic changes arise spontaneously in an early embryo or the sperm and/or egg that combine to create the embryo. Again, the majority of these gene changes do not cause autism by themselves. They simply increase the risk for the disorder.

Autism’s Environmental Risk Factors

Research also shows that certain environmental influences may further increase – or reduce – the risk for developing autism in people who are genetically predisposed to the disorder. However, the increase or decrease in risk appears to be small for any one of these risk factors:

Increased Risk

  • Advanced parent age (in either parent)
  • Pregnancy and birth complications such as extreme prematurity (before 26 weeks), low birth weight, or multiple pregnancies
  • Pregnancies spaced less than one year apart

Decreased Risk

Prenatal vitamins containing folic acid, taken before, at conception and through pregnancy have been shown to decrease the risk of a baby developing autism.

No Effect On Risk

Vaccines. Scientists have conducted extensive research over the last two decades to debunk the myth that there is any link between childhood vaccinations and autism. The results of this research is clear: vaccines do not cause autism.

How Genetic and Nongenetic Influences Give Rise to Autism

Most appear to affect crucial aspects of early brain development. Some appear to affect how brain nerve cells or neurons communicate with each other. Others appear to affect how entire regions of the brain communicate with each other.

Symptoms and Signs of Autism in Toddlers and Adolescents by Category

Social Communication and Interaction Skills

  • Avoids or does not keep eye contact
  • Does not respond to name by 9 months of age
  • Does not show facial expressions like happy, sad, angry or surprised by 9 months of age
  • Does not play simple interactive games like patty cake by 12 months of age
  • Uses few or no gestures by 12 months of age (for example, does not wave goodbye)
  • Does not share interests with others by 15 months of age (for example, shows you an object that they like)
  • Does not point to show you something interesting by 18 months of age
  • Does not notice when others are hurt or upset by 24 months of age
  • Does not notice other children and join them in play by 36 months of age
  • Does not pretend to be something else, like a teacher or superhero, during play by 48 months of age
  • Does not sing, dance or act for you by 60 months of age

Restricted or Repetitive Behaviors or Interests

  • Lines up toys or other objects and gets upset when order is changed
  • Repeats words or phrases over and over
  • Plays with toys the same way every time
  • Is focused on parts of objects (for example, wheels)
  • Gets upset by minor changes
  • Has obsessive interests
  • Must follow certain routines
  • Flaps hands, rocks body, or spins self in circles
  • Has unusual reactions to the way things sound, smell, taste, look or feel

Other Related Characteristics

  • Delayed language skills
  • Delayed movement skills
  • Delayed cognitive or learning skills
  • Low muscle tone
  • Hyperactive, impulsive, and/or inattentive behavior
  • Epilepsy or seizure disorder
  • Unusual eating and sleeping habits
  • Gastrointestinal issues (for example, constipation or diarrhea)
  • Unusual mood or emotional reactions
  • Anxiety, stress, or excessive worry
  • Lack of fear or more fear than expected
  • A compulsive need to eat non-food items