How to Get an Autism Diagnosis

A step-by-step guide to understanding autism evaluations, what to expect, and how to take the next steps with confidence.

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A Diagnosis Opens Doors

Getting an autism diagnosis for a child is an essential step in ensuring they get the support they need. Yet, it’s common to feel overwhelmed as you navigate the autism testing process. You may have questions about whether a child is the right candidate for an autism evaluation, who can diagnose autism, and what an autism assessment involves.

If this sounds familiar, you’ve come to the right place. Here, we’ll take you step-by-step through everything you need to know about how to get an autism diagnosis. The autism diagnosis process can be stressful at times, but knowledge is power. This guide will answer your most pressing questions and will help make the journey as smooth as possible.

Understanding Autism

Autism, also referred to as autism spectrum disorder (ASD), is a neurobehavioral condition that impacts how a child behaves, communicates, socializes, and experiences their sensory environment.

The CDC estimates that 1 in 31 children (3.2%) has ASD. Each autistic person is a unique individual, and autism symptoms often vary from one person to another. Autism is also a lifelong condition, and many people require support to help them manage its challenges.

It’s normal to feel worried about a child’s symptoms, especially before they have a formal diagnosis. You should know that you aren’t alone. Feeling stressed and uncertain as you begin the autism diagnosis process is completely understandable.

ACES is here for you as you move through the next steps, with evidence-based information, support, and resources. 

Additionally, some studies suggest less synaptic pruning in autistic brains, leading to more neural connections than in neurotypical individuals and stronger pattern recognition or more intense memory. These unique brain characteristics can affect communication, adaptability, and create unique strengths.

Woman wearing glasses and a beige shirt sitting closely with a young girl with bangs, both looking at something off-camera.

Early Signs of Autism by Age

Autism symptoms can vary significantly from one person with autism to another, which is why it’s considered a “spectrum disorder.” 

There is a wide spectrum of possible autism symptoms, which can range from milder to more severe. Not only that, but the way autism is experienced is a little different from person to person. Symptoms can also change over time, from early childhood through later childhood and beyond.

Nevertheless, there are some basic symptoms that are typically seen in early childhood, like a speech delay, which can be a sign of autism. These indicators are considered “red flags” for autism, meaning children with these signs are more likely to be diagnosed with autism.

Autism “red flags” include:

  • Coping with changes in routine
  • Trouble communicating and interacting with others
  • Repetitive behaviors and routine

Autism Symptoms by Age

Autism manifests differently depending on how old a child is. Here’s a breakdown of childhood autism symptoms by age.

Babies (Birth to 12 months)

  • Lack of eye contact or makes very little eye contact
  • Little or no response to sounds, emotions, or facial expressions of caregivers
  • Very little babbling or early speech sounds
  • May not like being touched or cuddled
  • May not respond to their name by 12 months
  • May not wave or point at things
  • Highly sensitive to sensory stimulation, like itchy clothing, loud noises, or bright lights
  • Alternatively, a child may seem to underreact to sensory stimulation

Toddlers (1-2 years)

  • Delayed speaking
  • Very distressed when daily routines change
  • Repetitive behaviors during play, such as obsessively arranging toys
  • Sensory aversion to day-to-day tasks, like getting dressed, brushing teeth, and eating
  • May also seek out sensory experiences
  • Trouble following instructions
  • Repetitive body movements, such as flapping arms 

Young children (ages 2-5)

  • Often repeating words and phrases over and over
  • Hyper-fixation on certain hobbies or interests
  • Less interest in pretend play
  • More frequent or intense tantrums than other kids their age
  • Trouble interacting with other children
  • Much more picky eating than peers 

Older children (elementary school and beyond)

  • Feeling overwhelmed by social situations and needing extra time to recover
  • Frequently not understanding social cues and feeling misunderstood by peers
  • May take things literally and may not understand sarcasm or irony
  • May come across as rude to others because of a more direct style of interacting
  • May be louder in social situations or interrupt frequently
  • May come across as inflexible and unable to adapt to changes
  • May have trouble behaving or managing school
  • May be more likely to be bullied at school
  • May have trouble making friends or seeming lonely
  • May feel easily overwhelmed
  • May experience mental health challenges, like anxiety and depression 

Autism Screening vs Autism Diagnosis

As you navigate the autism diagnosis process, you may hear terms like “autism screening” and “autism diagnosis” used almost interchangeably. However, it’s important to understand that both of these help clinicians better understand a child’s symptoms—and that they are different.

“Autism screening” tells you whether a child might be a good candidate for an “autism assessment,” while an “autism diagnosis” is when a child officially becomes diagnosed with autism.

Let’s take a closer look at these two aspects of autism assessment and the critical distinctions between them.

What is autism screening?

Screening for autism is not the same as an autism diagnosis. Screening simply tells a child’s healthcare provider that they may have some signs of autism. A positive screening—along with other symptoms and tests—may lead a healthcare provider or other clinician to encourage a family to pursue a more formal autism diagnosis.

Most early autism screening happens at a child’s well visits with their pediatrician. Even when a child is a baby, their pediatrician asks caregivers questions about the child’s communication. For example, they may ask if a baby is smiling yet, or whether they have begun to wave or point.

Formal autism screening: 18 to 24 Months

The American Academy of Pediatrics (AAP) recommends that all children—whether they are showing signs of autism or not—be screened for the condition between 18 and 24 months. This recommendation is due to the fact that the earlier support services are started for children with developmental and behavioral delays like autism, the greater the benefit to the child.

There are also various autism screenings available for children. The AAP doesn’t specify which autism screening should be used, but some common examples include:

  • Communication and Symbolic Behavior Scales (CSBS)
  • Ages and Stages Questionnaires SE-2 (ASQ-SE2)
  • Parents' Observations of Social Interaction (POSI)
  • Modified Checklist for Autism in Toddlers—Revised with follow-up (M-CHAT-R/F)

The most commonly used autism screening tool is the Modified Checklist for Autism in Toddlers. It contains 23 questions, and parents or caregivers fill it out in the doctor’s office. It includes questions about a child’s communication, social skills, responsiveness, and sensitivities.

If a child has a positive screening for autism, their pediatrician will likely recommend further testing, which may include a formal autism diagnosis.

Sometimes a child will not get a positive screen for autism, but a caregiver may still have concerns. Autism screenings occasionally miss autism cases, so it’s important to discuss your concerns with a pediatrician to see if continuing to pursue an autism diagnosis is right.

What is an autism diagnosis?

Unfortunately, autism can’t be diagnosed with a simple blood test. When a clinician diagnoses someone with autism, they are looking at several different factors at once, including:

  • Caregiver’s descriptions of a child’s development
  • Observation of a child’s behavior by a clinician or a team of clinicians
  • Diagnostic autism testing
  • Medical tests

Autism diagnoses also often happen over the course of several days, weeks, or months. A child might be evaluated by a group of healthcare providers, including psychologists, occupational therapists, speech therapists, or pediatricians. A child might be observed at play, in school, or in other familiar environments.

There are also various diagnostic tests that might be used during an autism diagnosis. Likewise, a pediatrician might order certain medical tests to rule out other medical conditions that might be causing the child’s symptoms, or to understand how other medical conditions are contributing to or interacting with the child’s autism.

After this information is gathered, the child’s healthcare team will determine whether the child meets the diagnostic criteria for autism, as outlined in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5).

This is when a child is formally diagnosed with autism. 

Why the distinction between diagnosis and screening matters

It’s important that caregivers understand the difference between screening and diagnosis for autism.

Screenings can’t diagnose

It’s essential to keep in mind that if a child is screened for autism at the pediatrician’s office and it comes up positive, that doesn’t mean they’ve been diagnosed with autism. Screening tests don’t tell you that a child doesn’t have autism. They are simply a starting point for a more thorough assessment and diagnosis.

If you want to know for sure whether a child has autism, you need to seek a diagnosis, rather than relying on screenings.

Beware of online autism screenings.

You should also be aware of misleading online screenings for autism. These are often websites that ask a few simple questions about yourself or a child to tell you whether or not autism is a possible concern.

Many people mistake this for an informal diagnosis, but this is not the case at all. Online screenings that typically last 5 to 15 minutes aren’t diagnoses, and they often aren’t reliable autism screenings.

Deep Dive Section

The Autism Diagnosis Process: Step by Step 

Now that you have a better understanding of autism, autism symptoms, and the initial screening process, let’s take an in-depth look at the autism diagnostic process. 

Initial autism diagnosis concerns

Sometimes a child is screened for autism during a well visit at their pediatrician's office. But if you have concerns about a child and they haven’t recently been screened for autism—or if you feel concerned despite a negative screening—you can ask for a formal screening of a child at any time.

Usually, pediatricians do these screenings. Pediatricians are a reliable go-to healthcare professional for these concerns because they know the child’s full health and medical history. Other providers can also do these screenings, including other doctors, nurses, or other medical providers, as well as professionals and experts in a child’s school or community. 

Finding a clinician for an autism diagnosis

When it comes to a formal diagnosis for autism, you need to select a licensed professional who is highly trained in diagnosing autism. One place to start is to ask a child’s pediatrician for a referral. You can also ask the child’s health insurance company for a referral to an in-network professional who can diagnose autism. In addition, in the state of California, there are Regional Centers that can assist with finding a diagnostician and locating other helpful services in your area.

As mentioned previously, there are various healthcare professionals who are qualified to conduct autism diagnoses. These include:

  • Pediatricians
  • Developmental pediatricians
  • Neurologists
  • Psychologists
  • Psychiatrists

Specifically, you may want to find a provider who is trained to administer the most common autism diagnostic tests, which include the ADOS (Autism Diagnostic Observation Schedule), ADI-R (Autism Diagnostic Interview-Revised), and CARS (Childhood Autism Rating Scale) diagnostic tests.

The quality of autism diagnostic evaluators varies. It’s best to choose someone who is licensed, works at a children’s hospital or autism center, and has a track record of working with a significant number of children with autism.

Comprehensive evaluation

Every autism diagnosis is a little different, but most include the following elements:

  • Interviews with the child and observation of them at play and during other activities
  • Interviews with caregivers
  • Evaluative diagnostic tests
  • Medical tests and health assessments

The core of an autism diagnosis is an autism diagnostic test. There are several tests that are used to diagnose autism, but the three most commonly used ones are:

  • ADOS (Autism Diagnostic Observation Schedule): a semi-structured, play-based assessment that lasts for 40 to 60 minutes
  • ADI-R (Autism Diagnostic Interview-Revised): a structured interview of the parents or caregivers of the child who is being evaluated for autism
  • CARS (Childhood Autism Rating Scale): a scoring system that helps determine the severity of a possible autism diagnosis, based on observations of a child’s behavior.

Other possible diagnostic tests include:

  • GARS-2 (Gilliam Autism Rating Scale-Second Edition)
  • SRS-2 (Social Responsiveness Scale-Second Edition)
  • SCQ (Social Communication Questionnaire)

 Some tests and assessments a provider may include as part of an autism diagnosis include:

  • A full medical exam
  • Medical history and family history
  • Hearing tests
  • Vision tests
  • Neurological exams
  • Cognitive testing
  • Language assessment tests
  • Adaptive behavior assessments

Begin the process of setting up services with ACES

Autism Results and Diagnosis

Once a child’s diagnostic testing is done, they will get the results from their provider. Getting results usually involves a meeting with the clinician who did the testing to discuss the results. There is also a written report that describes those results.

Sometimes a provider will use more than one test. Which tests will be used will depend on a child’s age, symptoms, and the best match for the child. These tests can take several hours to complete and sometimes require multiple visits to the diagnostician.

After an autism assessment, a child may:

  • Be diagnosed with autism
  • Be diagnosed with a condition other than autism
  • Not diagnosed with autism, but referred to a specialist for further testing
  • Not be diagnosed with any condition

What comes after an autism diagnosis?

After a child receives an autism diagnosis, their clinician will discuss the next steps, including support that may be helpful for the child. The diagnostician may provide information on which types of therapy would be helpful for a child and how intensive the therapy should be.

The types of therapies and interventions they may recommend may include:

  • Speech therapy
  • Occupational therapy
  • ABA therapy (Applied Behavior Analysis Therapy)
  • IEP plans (Individualized Education Programs) 

Post-diagnosis: ABA therapy

If a child’s evaluator recommends ABA therapy, ACES ABA can help ensure that the child receives compassionate, comprehensive care targeted to their specific needs. While ACES doesn’t diagnose autism, once a child has an autism diagnosis, ACES can take it from there.

ACES ABA therapy includes:

  • Before services begin, ACES provides comprehensive assessments, goal setting, and individualized therapy plans
  • ACES provides reports that outline what therapy will involve and how many hours to expect to meet a child’s goals
  • ACES treatment planning is based on your priorities and the child’s specific needs
  • ACES provides coordination with other providers, including teachers, social workers, speech therapists, and occupational therapists

Meeting the Official Diagnostic Criteria: DSM-5

In order to be officially diagnosed with autism, you must meet the criteria for autism outlined in the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5). In 2013, the diagnostic criteria for autism were expanded from an earlier version. In the new edition, subtle traits of autism are more widely recognized, and autism is now thought of as more of a spectrum than previously.

According to the DSM-5, in order for a child to be diagnosed with autism, they must have persistent deficits in all three listed aspects of social communications and interactions and at least two out of four listed restricted and repetitive behaviors.

Social communications and interactions

The three social communications and interactions deficits include:

  1. Difficulties with social reciprocity, like back-and-forth conversation, and difficulties with expression or understanding emotions
  2. Challenges in non-verbal communication during social interactions
  3. Problems developing and maintaining relationships with people other than caregivers

Restricted and repetitive behaviors

The four possible restricted and repetitive behaviors are:

  1. Repetitive motor movement, which may include repetitive use of objects or repetitive speech
  2. Inflexible routines, an intense need for sameness, or ritualized patterns of behaviors (verbal or non-verbal)
  3. Hyper-fixation and abnormal intensity in certain specific interests
  4. Hypersensitivities to sensory stimuli or insensitivities to sensory stimuli 

Why Comprehensive Autism Evaluation Matters

There are several important reasons why getting a comprehensive evaluation and diagnosis for autism matters.

Screenings alone are not in-depth or diagnostic.

Some people do an online autism screening or get a screening at a doctor’s office, and don’t fully complete the evaluation process for autism. Using or mistaking an autism screening for an autism diagnosis is like a person with type 2 diabetes answering a few online questions and thinking they’ve been diagnosed with diabetes, as opposed to going to a doctor and getting actual bloodwork and a medical exam. An actual autism diagnosis involves licensed medical professionals, is a several-hour-long process, and can’t be done via a 15-minute assessment. 

Diagnoses are necessary for autism services to be covered

Importantly, if a child requires services for autism, such as ABA therapy, most health insurance companies will only cover these services if a child has received a formal autism diagnosis from a healthcare professional.

A comprehensive evaluation leads to comprehensive treatment

An autism diagnosis doesn’t just tell you whether or not you have autism. It tells you how severe the autism is, what challenges are specific to your case, and what support is needed. A thorough evaluation and diagnosis for autism sets you up for success.

Here are some tips:

  • Ask the clinician how long to expect each assessment to take
  • Find out what the assessments will involve and who will be present during each assessment
  • When allowed, bring familiar toys and snacks for the child to keep them occupied
  • Prepare the child for what to expect during the assessment, including the types of activities that may occur, questions that may be asked, and who will be in the room with them.
  • Make sure that the child gets enough sleep before the assessment.

It’s also necessary to take care of yourself. As a caregiver, if you are stressed or scared, the child in your care may absorb this. Seeking support for yourself during this process by talking to a trusted friend or therapist can be beneficial. Employing relaxation methods like deep breathing and visualization can be helpful, too. 

Preparing a Child for an Autism Evaluation

Sometimes, autism evaluations can be overwhelming and stressful for children. But caregivers can take steps to minimize this and make the evaluation a more positive experience. 

To learn more about how ABA therapy works and how ACES can help after a child’s autism diagnosis, please contact the ACES Welcome Center

References

Data and Statistics on Autism Spectrum Disorder. CDC. 2025.

Understanding Autism: Information for Families. American Academy of Pediatrics. 2025.

What are the symptoms of autism?. National Institute of Child Health and Human Development. 2025.

Autism symptoms: Common signs of ASD in children. UNICEF. 2025.

How Pediatricians Screen for Autism.

The Modified Checklist for Autism in Toddlers, Revised with Follow-Up. M-CHAT. 2026.

How Is Autism Diagnosed?

Screening for Autism Spectrum Disorder. CDC. 2025.

Santos, C. L. D., Barreto, I. I., Floriano, I., Tristão, L. S., Silvinato, A., & Bernardo, W. M. (2024). Screening and diagnostic tools for autism spectrum disorder: Systematic review and meta-analysis. Clinics (Sao Paulo, Brazil), 79, 100323.

Autism Diagnosis in Primary Care. American Academy of Pediatrics. 2025.

Understanding Autism: Information for Families. American Academy of Pediatrics. 2025.

Clinical Testing and Diagnosis for Autism Spectrum Disorder. CDC. 2025.

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Common Questions

Debating getting a diagnosis can bring up a lot of feelings. We’re here to answer your questions so you can have the confidence to take the next step.

Understanding Autism

Caring for a child with autism can feel like an ongoing process of acceptance and grief, confidence and uncertainty. Support and understanding along the way can make a profound difference in the potential quality of life.

Where to Go From Here

Now that you have a better handle on how to get an autism diagnosis and what to expect, you are ready for the next step: making an appointment with a healthcare professional to start the process. Remember that the process can take a while and has several steps, including screenings, evaluation, and diagnosis. Grace and patience can go a long way as you move through these steps. And, while early intervention for autism means a child will begin their journey sooner, it’s never too late to be proactive and take the first steps for a diagnosis. 

If you need support as you begin—or at any step in the process—don’t hesitate to reach out to ACES. We are here for you as you get your diagnosis and digest the results. We can help you develop a solid, compassionate, and child-centered plan to ensure the child in your care grows, gains essential skills, and thrives.