Diagnosing autism spectrum disorder (ASD) can be difficult as there is no specific test to diagnose this condition. While online tests may help identify ASD characteristics, they are not diagnostic tools. Only an autism specialist can diagnose ASD with assessments, although online tests may help.

In childhood, ASD symptoms can present by 3 years of age. However, some people may not receive a diagnosis until they reach adulthood.

Some people could use an online test to determine whether they or their children have the disorder. However, they generally do not provide an accurate diagnosis.

In this article, we examine autism testing in-depth and take a deeper look at online testing accuracy.

A caregiver and a child taking an online autism test. While online autism tests may help, only an autism specialist can diagnose autism.Share on Pinterest
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ASD is a neurological condition that may cause differences in how a person socializes, behaves, and communicates. People with autism can be different from one another, which can make diagnosis difficult.

According to the Centers for Disease Control and Prevention (CDC), in 2016, the prevalence of ASD in United States children was around 1 in 54.

The current Diagnostic and Statistical Manual of Mental Disorders (DSM-5) lists ASD as an umbrella term with different levels that indicate the support a person may need.

While experts used to think ASD was more common in males than females, some research suggests that the condition may be underdiagnosed in females.

There is no cure or known trigger for ASD, although there is some consensus that genes play a role. However, many people with autism value neurodiversity and do not believe there is a need for a cure.

The autism spectrum can present quite differently from one person to another. However, people with autism may generally experience challenges with communication, social interaction, restricted or repetitive behaviors, and sensory processing.

While some of these symptoms may indicate ASD in people, they can also point to other conditions or diagnoses.

Usually, an autism diagnosis happens in early childhood. However, as symptoms widely differ, the condition can be challenging to diagnose. Some people may not receive a diagnosis until they are adults.

Currently, there is no official test to diagnose ASD. However, the following experts may be able to confirm this condition in people:

  • psychologist
  • neuropsychologist
  • neurologist
  • psychiatrist
  • developmental pediatrician

Below are some examples of the tests for autism:

Developmental screening

Doctors screen children for developmental progress as they grow. Screening requires regular visits with a pediatrician.

If a parent or caregiver has concerns about a child’s development, their pediatrician may refer them to a specialist, who may conduct the following evaluations:

  • hearing tests
  • Modified Checklist for Autism in Toddlers (M-CHAT)

The M-CHAT identifies the need for further testing if a child’s scores indicate a high risk for autism. It is not a diagnostic tool, but a screening technique that specialists use to determine who needs a more thorough ASD evaluation.

No single test can definitively diagnose ASD. Other screening tools may include:

  • Ages and Stages Questionnaires
  • Communication and Symbolic Behavior Scales
  • Parents’ Evaluation of Developmental Status
  • Pervasive Developmental Disorders Screening Test-II
  • Screening Tool for Autism in Toddlers and Young Children
  • Social Communication Questionnaire

Healthcare providers may also order additional tests if they suspect a physical problem, such as lead poisoning or a genetic disorder, is causing similar symptoms to ASD.

Behavioral evaluation

Behavioral evaluation is typically the next step if a child scores highly on the M-CHAT or a different screening tool. Tests during this stage may include assessments from:

  • child psychologists
  • neurologists
  • language and speech pathologists
  • developmental pediatricians
  • occupational therapists

Specialists use a combination of exams and screening tools to make a diagnosis.

An evaluation may involve:

  • observing play and parent-child interaction
  • taking a detailed history
  • physical exams
  • developmental skill assessment to determine if there is any language, motor, social, or cognitive impairment
  • hearing tests
  • language evaluation

Diagnostic tools at this stage may include:

  • Autism Diagnostic Interview-Revised
  • Autism Diagnostic Observation Schedule
  • Autism Spectrum Rating Scale
  • Childhood Autism Rating Scale
  • Gilliam Autism Rating Scale – Second Edition
  • Social Responsiveness Scale

The DSM-5 also includes criteria for diagnosing ASD.

Genetic testing

Genetic tests cannot definitively diagnose ASD. It is possible to test for certain biomarkers that may indicate the condition, but this technique is generally not a useful tool.

Online tests are not diagnostic tools. However, they may help a person determine whether they should speak to a doctor or specialist regarding ASD.

Tests from reputable, official organizations are only screening tools. They cannot provide a person with an official ASD diagnosis.

For example, the M-CHAT is a widely-used online screening tool. It can help parents and caregivers identify whether their child might have ASD, but it cannot provide a definitive diagnosis.

However, in certain cases, online tests may assist specialists in diagnosing ASD, but only as part of a more comprehensive assessment process.

Online screening tools can help parents and caregivers decide whether to seek further specialist help.

If a person wants to confirm an ASD diagnosis either in themselves or a child, they should speak to a doctor. Parents should talk to their pediatrician if they have concerns about their child having ASD.

A doctor may provide additional screening tests. Depending on the results, they may refer people to other specialists.

There is no cure for autism, but many people with the condition can live independent lives.

When a child receives a diagnosis, it is possible to include educational and behavioral interventions. These can help children with their social and language skills. Examples of treatment approaches include:

  • Applied behavior analysis: Uses behavioral reinforcement strategies to encourage certain behaviors. The different techniques include:
    • Discrete trial training
    • Early intensive behavioral intervention
    • Pivotal response training
    • Verbal behavior intervention
  • Occupational therapy: Helps children with fine and gross motor skills.
  • Sensory integration therapy: Helps those with ASD who are sensitive to bright lights, certain sounds, or smells to cope with sensory information.
  • Floortime: Also known as developmental, individual differences, relationship-based approach. A therapy technique where the parent, caregiver, or therapist follows the child’s lead in creating meaningful interactions, which promotes their development.

Other treatment approaches include social skills and communication interventions.

Doctors may also prescribe medication to treat certain symptoms of ASD, including:

Doctors may also prescribe antipsychotic medications to people with ASD who have severe behavioral problems.

ASD is a common neurological condition. However, it affects people in different ways, which can make diagnosis difficult.

Early diagnosis of ASD can help those on the autism spectrum find support and learn to live independently. A diagnosis can also help others understand how to respond to certain behaviors.

While online testing is an attractive option for people who want to find out if they or their child have ASD, it is no substitute for an official diagnosis from a qualified medical professional.

Diagnosis involves a combination of evaluation tools. Only a professional can accurately diagnose ASD, and even then, the assessment process can be challenging.