Autism Diagnosis in Children: Why Proper Assessments Take Time

Autism diagnosis in children requires comprehensive evaluation, not a brief pediatric screening. A proper assessment includes behavioral observation across multiple settings, a 36-page developmental history, and standardized tools including the ADOS-2. In clinical practice a thorough autism evaluation can take 15 to 20 sessions of 90 minutes each, particularly when building the trust needed for a child to perform authentically and reveal their true strengths and challenges.

Pediatricians use about 10 minutes to evaluate children between 18 and 36 months old for autism in according to the research. They missed the symptoms almost entirely.

How could they possibly have seen them?

The setting was highly structured. The focus was entirely on the child. In all likelihood, only adults were present, which is actually an ideal situation for many kids on the spectrum. You won’t see what you need to see in a calm, controlled room with no social complexity, no peers, and no unexpected demands.

I’ve seen this same problem with ADHD evaluations; both disorders are routinely missed or misdiagnosed because the evaluation wasn’t thorough enough. Symptoms of ADHD overlap with at least 17 other diagnosable disorders, one of which is autism spectrum disorder. Both conditions require intensive, individualized assessment to identify and treat the true picture. Ten minutes simply doesn’t cut it.

Every Child is a Puzzle

Every person is a puzzle. The key to understanding children, especially children on the autism spectrum, is spending enough time with them that they come to trust you. They need to know, absolutely know, that you’re there to help and not to humiliate them. They need to know you’ll tell them what’s going on and what you’re going to do about it.

That doesn’t happen in 10 minutes.

When parents called to ask about an assessment and decided they wanted to come in, I’d see them for 60 to 90 minutes for an initial consultation. I would then arrange at least two “blind” classroom observations, blind because my student hadn’t met me yet. I watched each child in the classroom and in unstructured settings on at least two separate occasions. Invaluable.

Why do Autism Assessments & Diagnosis Take so Long?

In 25 years of assessing children, teens, and young adults in private practice, I found that getting all the information I need, without wounding a person with autism in the process; can take 15 to 20 sessions of 90 minutes each.

Before the assessment even begins, I ask parents to bring their child in simply to meet me and see my office. They are in charge. If they decide they like me and want to work with me, we move forward. In all those years, only one child refused, and he wasn’t autistic. He was a 14-year-old hardened gang member in chains, already on the wrong road.

I asked parents to refer to me only as ‘Miss Claudia’ because ‘doctor’ means something very specific and often frightening to children, whereas ‘learning detective’ is a far more accurate and welcoming description of what I actually do.

Building Trust & Reducing Anxiety Before Testing

For children who are particularly anxious, and the autistic brain is, by nature, an anxious brain, I invite them to come in several times before we ever begin formal testing. We play games like Connect Four. They bring in their favorite things. Sometimes they just come to hang out for 20 minutes.

No matter how old the client is, they need time to adjust to the setting and to me. You cannot put a child in a chair and expect them to work to their full potential. They need to know where the bathroom is. They need to know where to put their snacks. They need to know what happens during their break. Anxiety will undermine the most competent examiner’s results.

For me, this process was never about getting results, it was about getting results I could trust, in order to plan services and supports that would actually build a child’s life.

Environment Matters More Than You Think

My office was large, comfortable, and deliberately warm. No stainless steel, no harsh fluorescent lights. Wood, fabric, and leather furniture. Pictures of my dog and my son to humanize me. Children frequently asked, ‘Do you live here?’

There were plenty of places to ‘slounge’ my word for the combination of sitting and lounging that kids naturally do when they feel safe. When we worked through tasks, we moved from the table and chairs to the sofas. Kids laid on the floor. One insisted on working from under the coffee table while I read questions from the social-emotional rating scales. I quickly made numbered cards so he could hold his arm out from underneath to answer. He struggled so deeply with acknowledging his emotions that he couldn’t face me and talk about his feelings at the same time. I adapted to meet him where he was.

Children were allowed to take off their shoes, wrap themselves in blankets, work by natural daylight or lamps. For many of my boys on the spectrum, preferred topics meant World War II. They brought in books. We discussed generals, battles, and weapons. I learned a tremendous amount. Whatever it took to make them comfortable, we did it. We worked, and worked hard.

What an Autism Diagnosis Involves & What Gets Tested?

The following is my assessment plan for elementary, middle, and high school students on the spectrum:

To Measure Learning Potential and Academic Problem-Solving (IQ):

• Wechsler Intelligence Scale for Children–6th Edition
• Wechsler Adult Intelligence Scale–5th Edition (ages 16+)
• Leiter International Performance Scale–3rd Edition (language free)

To Measure Academic Achievement in Reading, Math, and Writing:

• Wechsler Individual Achievement Test-4^th Edition
• Gray Oral Reading Tests–5th Edition
• Nelson-Denny Reading Tests (high school/college)
• Orleans-Hanna Algebra Prognosis Test–3rd Tests of Written Language-4th Edition
• Tests of Written Language-4^th Edition (**if phonetic competency is in question, administer the Dyslexia Index subtests of the Wechsler Individual Achievement Tests-4^th Edition**)

To Measure Processing Skills:

• Test of Memory and Learning–2nd Edition
• The Listening Comprehension Test–2nd Edition / Adolescent version is the Listening Comprehension Test-Adolescent Normative Update
• Rey Complex Figure and Recognition Trial
• Bender Visual Motor Gestalt–2nd Edition
• Conners 4 Rating Scales/Long Form (teachers, parents, students 9+)
• Woodcock-Johnson Tests of Achievement–4th Edition (Fluency subtests)
• Behavior Rating Inventory of Executive Functioning–2nd Edition (parents, teachers, students 11+)

To Measure Social-Emotional Development and Functioning:

• Behavior Assessment Scale for Children–3rd Edition (parents, teachers, students)
• Revised Children’s Manifest Anxiety Scale–2nd Edition
• Reynolds Child Depression Scale–2nd Edition / Reynolds Adolescent Depression Scale
• Millon Pre-Adolescent Clinical Inventory / Millon Adolescent Clinical Inventory
• Gilliam Autism Rating Scale–3rd Edition (parents)
• Test of Problem-Solving / Elementary–3rd Edition-normative update/ Adolescent–2nd Edition
• Autism Diagnostic Observation Schedule–2nd Edition (ADOS-2)
• Social Responsiveness Scale–2nd Edition (parents and teachers)
• Vineland Adaptive Behavior Scale–3rd Edition (Parent Interview Edition)

Parents also completed a 36-page developmental history documenting their child’s life from conception to the present. I conducted an extensive review of all records school, medical, and private clinical and documented the history of services received and gaps in support.  This developmental history is in the resource section of Sock Puppet Shrink

Why Autism Diagnosis Numbers Are Only Part of the Story

Parents often ask: “Isn’t that a lot of testing?”

Yes. It is.

My strategy to prevent frustration, boredom, and motivational collapse was a revolving door of tasks. A reading task for 10 minutes, then a drawing task, then math, then part of a rating scale, constantly rotating. This kept dopamine flowing through the novelty of the schedule.

I always told my students which tasks needed to be completed for the day and asked them what they wanted to tackle first. Once finished, I asked what they wanted next. When it was time for rating scales, which I never called “rating scales,” I’d say, “we move to the sofa.” They quickly figured out to ask for the “sofa stuff.” Feet on the coffee table. Working.

But here’s what I want every parent to understand: the real data from an assessment isn’t in the numbers. It’s in the “how did they do it?”

By administering every test myself, I gathered behavioral observations that no computer scoring system can capture. I could answer:

• What strategy did she use to approach this task?
• How well did he tolerate frustration here?
• What was her stamina, persistence, and attention span for this specific type of demand?
• Did he have metacognitive skills: awareness of his own problem-solving approaches?
• Did she have metamemory skills: awareness of her own memory strategies?
• Could he reason inductively (parts to whole) and deductively (whole to parts)?
• Did she demonstrate emerging higher-order thinking skills: cause and effect, generalization, analysis, drawing conclusions?

This is Bloom’s revised taxonomy in action. And this is the level of understanding I needed before I could have any confidence in a plan for a child.

After testing, I met with parents for a detailed feedback session and with the child for a highlights session focused entirely on what will happen next to help them. I wrote a comprehensive report with a subtest-by-subtest analysis; essentially allowing parents to see their child completing each task through my eyes.

A Note on School Districts

After testing, I met with parents for a detailed feedback session and with the child for a highlights session focused entirely on what will happen next to help them. I wrote a comprehensive report with a subtest-by-subtest analysis; essentially allowing parents to see their child completing each task through my eyes. Running them through 4 hours of testing is not, in my opinion, the way to get accurate results.

What to Look for in an Autism Doctor?

Nothing less than this level of thoroughness should satisfy you as a parent.

If your child needs an autism assessment, do your best to choose a clinician who:

• Is genuinely sensitive to your child’s unique needs
• Has real experience in school settings
• Understands both educational and developmental issues
• Takes the time to build trust before testing begins

Your child deserves someone who sees them as a puzzle worth solving, not a checklist to complete in 10 minutes.

Concerned about your child’s development and wondering whether a comprehensive evaluation is the right next step? Browse more on mental health and special needs support:

Autism in College

Autism Diagnosis Frequently Asked Questions (FAQs)

How is Autism Diagnosed in Children?

Autism diagnosis requires comprehensive evaluation, including behavioral observation, developmental history & standardized tools like the ADOS-2 (Autism Diagnostic Observation Schedule 2nd Edition). Brief screenings alone are not sufficient.

Why can’t Autism be Diagnosed in a Short Visit?

Short visits lack enough time to observe social behavior, communication patterns, and emotional regulation across settings.

What Tests are Used in Autism Diagnosis?

Common tools include the WISC-V, BASC-3</a>, and adaptive functioning scales.

How Long Does an Autism Diagnosis Take?

Comprehensive evaluations may take multiple sessions over several weeks to gather accurate, reliable data.