Understanding autism

Autism is a developmental difference in how a person communicates, senses the world, and processes information. It is lifelong, it is not caused by parenting, and it is not something a child grows out of — though what a child needs changes a great deal over time.

1 in 31US 8-year-olds identified with autism in the CDC's most recent tracking data (2022 surveillance year, published 2025)
47 monthsMedian age of diagnosis — just under four years old, though reliable diagnosis is possible by two
~4xMore often identified in boys than girls, with growing evidence that girls are under-identified
18 & 24 moAges the American Academy of Pediatrics recommends screening every child for autism

What clinicians are actually looking at

A diagnosis rests on two areas, both present from early childhood, both affecting daily life.

Social communication and interaction

  • Back-and-forth conversation works differently — it may be one-directional, delayed, or intensely focused on a topic
  • Eye contact, gesture, facial expression and tone may not line up the way others expect
  • Friendships and imaginative play with peers can be hard to start or sustain
  • Speech may be delayed, absent, scripted, or highly advanced — all of these are autism

Repetitive behaviours and sensory differences

  • Stimming — rocking, hand movements, humming, pacing — which regulates the nervous system
  • Strong need for routine and real distress when it breaks
  • Deep, sustained interests that can become genuine expertise
  • Sensory sensitivity or seeking: sound, light, texture, taste, smell, movement, pain

Support levels, not severity. The current diagnostic manual describes Level 1, 2 or 3 for how much support a person needs in each area. Levels are a snapshot, not a ceiling — the same child can be Level 1 for one thing and Level 3 for another, and can move between them depending on stress, environment and age.

Getting an evaluation

  1. Say it out loud to your pediatrician

    Ask directly for a developmental evaluation referral and ask for it in writing. If you're brushed off with "let's wait and see," you can self-refer to the programs below without the referral.

  2. Call early intervention (under 3) or your school district (3+)

    Both are free, both are legally required, and neither needs a diagnosis first. Under three, your state's Part C program evaluates within 45 days of referral. Age three and up, a written request to the district starts a federally timed evaluation process.

  3. Get on the diagnostic waitlist at the same time

    Developmental pediatricians, child psychologists and neuropsychologists have long waits — often 6 to 18 months. Get on several lists at once, including university clinics, and take the earliest one.

  4. Bring evidence

    Videos of your child at home, notes on what you see and when it started, and reports from daycare or school. Clinic behaviour is not home behaviour, and video closes that gap.

  5. Ask for an interpreter, in writing

    Schools, early intervention programs and any healthcare provider receiving federal funds must provide free interpretation and translated documents. You do not have to bring a relative to interpret, and you should not have to rely on your own child.

  6. Read the report and ask for corrections

    The written report determines what services are funded. If it misses something you described, say so before it's finalised. Ask for the specific wording that supports the services you want.

Co-occurring conditions worth screening for

Autism rarely arrives alone, and several of the things that make life hardest are treatable conditions sitting alongside it. Ask about these directly.

ADHD

Very common alongside autism, and can be diagnosed together. Often the more disruptive of the two for school.

Anxiety

Affects a large share of autistic children. Frequently mistaken for "behaviour."

Sleep problems

Extremely common and it makes everything else worse. Worth treating first.

GI issues

Constipation and reflux are more common, and pain often shows up as behaviour, not complaint.

Epilepsy

Higher rates than the general population, often emerging in early childhood or adolescence.

Intellectual disability

Present in some but far from all autistic people, and testing is often unreliable in non-speaking children.

Feeding differences

Selective eating driven by sensory response, not defiance. A feeding therapist can help.

Dyspraxia / motor

Coordination and motor planning difficulties that affect handwriting, sport and self-care.