Understanding Autism: Levels, Diagnosis, and What Often Comes With It

Understanding Autism: Levels, Diagnosis, and What Often Comes With It

The terminology changed in 2013 and a lot of families are still working with the older map. Here’s how autism is described now, what the levels actually mean, and — the part most often overlooked — the treatable conditions that frequently travel alongside it.

One diagnosis, not several

Until 2013, autism was divided into separate diagnoses: autistic disorder, Asperger’s syndrome, PDD-NOS, and childhood disintegrative disorder.

The current manual merged these into a single diagnosis — autism spectrum disorder — because the boundaries between them were not applied consistently, and the same child could receive different labels from different clinicians.

Asperger’s syndrome is no longer a separate diagnosis. People diagnosed under the old system keep their diagnosis and many still identify with the term, which is entirely reasonable. New diagnoses are made as ASD.

The two core areas

A diagnosis requires differences in both:

Social communication and interaction — back-and-forth conversation, reading and using nonverbal cues, and developing and maintaining relationships appropriate to age.

Restricted, repetitive patterns — repetitive movements or speech, strong preference for routine and distress at change, intensely focused interests, and unusual responses to sensory input. Sensory differences are frequently the thing parents notice first: a child overwhelmed by noise, or seeking out particular textures and pressure.

Symptoms must be present in early development, though they may not become fully apparent until social demands exceed capacity — which is why some children are identified in preschool and others not until middle school.

What the levels mean

The diagnosis includes a support level, assigned separately for each core area. The levels describe how much support a person needs, not how “severe” their autism is or how intelligent they are.

• Level 1 — requiring support. Noticeable difficulty initiating social interaction; inflexibility causing meaningful interference.
• Level 2 — requiring substantial support. Marked difficulty even with supports in place; distress at change is obvious.
• Level 3 — requiring very substantial support. Severe difficulty; very limited initiation; great distress with change.

Two things worth knowing. Levels are not permanent — support needs change with development and intervention. And a child can be Level 1 for social communication and Level 2 for restricted behaviors; the profile is rarely uniform.

Early signs, by age

By 12 months: no babbling, no pointing or waving, no response to their name, limited eye contact.

By 18 months: no single words, no pointing to show you something interesting, no pretend play.

By 24 months: no two-word phrases, limited interest in other children, unusual repetitive movements.

At any age: loss of skills previously acquired. This always warrants prompt evaluation, regardless of anything else.

Later signs in children identified at school age: difficulty with peers despite wanting friendship, taking language very literally, strong need for routine, intense interests, and meltdowns after school from holding it together all day. Children who mask well — often girls — are frequently identified late, sometimes only after anxiety or depression brings them in.

Screening is routine

The AAP recommends autism-specific screening at the 18-month and 24-month well-child visits, in addition to developmental surveillance at every visit. The M-CHAT is the common tool.

A positive screen is not a diagnosis — it means further evaluation is warranted. You can also raise concerns at any visit; you don’t have to wait for a screening age.

The part most often missed: co-occurring conditions

This matters enormously in practice. Many of the things that make daily life hardest for an autistic child are separate, treatable conditions — and they’re frequently attributed to the autism and left alone.

• ADHD co-occurs very commonly. It’s now recognized that both can be diagnosed together, which wasn’t permitted under the older system.
• Anxiety is highly prevalent and often underestimated, partly because it can present as rigidity or behavioral escalation rather than expressed worry.
• Sleep problems affect a majority of autistic children. See how much sleep your child actually needs.
• Gastrointestinal problems — constipation, reflux, abdominal pain — are more common, and in a child with limited communication can present as a sudden behavior change. A child who becomes distressed for no apparent reason may be in pain.
• Feeding difficulties, including highly restricted eating driven by sensory sensitivity, with nutritional consequences worth monitoring.
• Epilepsy occurs at higher rates. Staring spells or unexplained lapses deserve evaluation.
• Intellectual disability in some but by no means all autistic people — and language ability and intellectual ability are not the same thing.

The practical point: a new or worsening behavior is worth a medical look before it’s treated as behavioral. Pain, constipation, poor sleep, and untreated anxiety are common and fixable causes of escalation.

Early intervention

Florida’s Early Steps program serves children under three, and you can refer your own child — you don’t need a physician’s referral or a diagnosis to request an evaluation. From age three, the school district takes over, whether or not your child is enrolled.

You don’t have to wait for a formal diagnosis to start services, and given that evaluation waitlists can be long, starting the referral in parallel is usually the right move.

What we do

We provide developmental screening at recommended intervals, refer for diagnostic evaluation, help with Early Steps and school district referrals, manage co-occurring ADHD, anxiety, sleep and GI problems, and coordinate ongoing care.

Our practice has more depth in behavioral health than most general pediatric offices, which means much of this can be managed here rather than referred out.

If you have concerns, raise them

The most common thing we hear from parents is that they waited because someone told them to. Bring it up.

Book an appointment at our Longwood or Apopka office, or contact us. If you have videos of the behaviors that concern you, bring them — they’re often more useful than a description.