Estimated reading time: 9 minutes
Introduction
If you're a parent or grandparent, you've probably heard the terms autism and ADHD more and more in conversations at schools, playgrounds, or doctor's visits. Both conditions are now widely recognised, and yet they're often confused. I've sat with other parents who say things like:
"My grandson has ADHD, but isn't it similar to autism?"
"My daughter's teacher thinks she has ASD Level 2, but I thought that was the same as ADHD."
These misunderstandings are common. While autism and ADHD share some overlapping traits—like difficulties with attention, social interaction, or impulse control—they are distinct conditions, each with their own challenges and strengths.
In this article, we'll unpack the key differences between autism and ADHD, how ASD levels (1–3) help describe autism, and why concepts like GDD (Global Developmental Delay) and developmental milestones in the EYLF are important when understanding your child's journey.
Table of Contents
What is Autism?
Autism Spectrum Disorder (ASD) is a neurodevelopmental condition affecting communication, behaviour, and social interaction. Signs are usually noticeable in early childhood, though the degree of support needed varies widely.
The term spectrum reflects this diversity. Some children may only need gentle nudges in social learning (Level 1 autism), while others may require substantial or very substantial support (ASD level 2 or ASD level 3) across communication, daily living, and learning (American Psychiatric Association, 2013).
What is ADHD?
Attention-Deficit/Hyperactivity Disorder (ADHD) is a neurodevelopmental condition primarily characterised by difficulties with attention, impulse control, and regulation of activity levels (CDC, 2022).
Unlike autism, ADHD is less about social communication differences and more about regulation—sustaining focus, controlling impulses, and moderating energy. ADHD often becomes noticeable once children start school, where demands for sitting still and concentrating become greater.
Autism: Levels of Support Needs
Autism is often described using levels of support:
| Level | Description |
|---|---|
| Level 1 autism: Needs some support | e.g., difficulty in social cues, but communicates verbally. |
| ASD Level 2: Requires substantial support | Noticeable language and behavioural challenges. |
| Autism Level 3 / ASD Level 3: Requires very substantial support | Minimal speech, reliance on strict routines. |
These levels of autism help professionals tailor support but do not predict potential. With the right environment, many children exceed expectations (Lord et al., 2020).
ADHD: Key Signs and Subtypes
ADHD is generally divided into three presentations (APA, 2013):
Predominantly inattentive:
Forgetful, easily distracted, struggles with sustained tasks.
Predominantly hyperactive-impulsive:
Restless, talkative, impulsive.
Combined presentation:
A mix of both inattentive and hyperactive-impulsive traits.
Unlike autism, ADHD does not involve restricted/repetitive behaviours or differences in social reciprocity. But it often co-occurs with learning difficulties or emotional regulation challenges.
Autism vs ADHD: Key Differences
Here's a simple way to frame it:
Autism (ASD):
Primarily about social communication differences and repetitive/restricted behaviours. ASD levels (1–3) reflect the amount of support needed.
ADHD:
Primarily about attention, impulse control, and activity regulation. Support varies, but there are no "levels" of ADHD like with autism.
Another way to put it:
Autism changes how a child connects with the world, while ADHD changes how a child regulates themselves in the world.
Autism, GDD, and Developmental Milestones (EYLF)
Families often ask whether missed developmental milestones automatically signal autism or ADHD. The truth is, it depends.
GDD (Global Developmental Delay):
Some toddlers miss milestones across multiple domains (motor, speech, social). This may later lead to an ASD diagnosis, but not always (Shevell et al., 2003).
EYLF (Early Years Learning Framework):
In Australia, educators use EYLF to track milestones like language, play, and problem-solving. This helps flag when a child may benefit from extra assessment.
Understanding these frameworks helps parents avoid panic while still seeking timely professional support.
Find Autism & ADHD Specialists
Connect with qualified professionals who can help assess and support children with autism or ADHD.
FAQs for Families
References & Further Reading
- American Psychiatric Association. (2013). Diagnostic and Statistical Manual of Mental Disorders (5th ed.). Washington, DC. (link)
- Lord, C., Elsabbagh, M., Baird, G., & Veenstra-VanderWeele, J. (2020). Autism spectrum disorder. The Lancet, 392(10146), 508–520. (link)
- Shevell, M., Ashwal, S., Donley, D., et al. (2003). Practice parameter: Evaluation of the child with global developmental delay. Neurology, 60(3), 367–380. (link)
- Leitner, Y. (2014). The co-occurrence of autism and ADHD: A review. Current Opinion in Psychiatry, 27(2), 91–95. (link)