Intellectual disability factsheet

Introduction

Intellectual disability (ID) is a lifelong condition that affects learning and behaviour.

Children with ID learn more slowly than other children. They may also have developmental delays early in life.

ID affects:

  • intellectual skills – meaning skills like learning, memory, problem-solving, and reasoning
  • adaptive behaviour - meaning everyday skills like talking, eating, dressing, toileting, and making friends.

ID can be caused by:

  • genetic conditions – for example, Down syndrome or Fragile X syndrome
  • head or brain injuries
  • infections around the brain, like meningitis
  • complications during birth, like not having enough oxygen.

 Signs and symptoms

Some children with ID show signs before five years old. They may have delays in reaching different developmental milestones. 

Other children with ID may not show signs until they start school, when learning and social differences become more noticeable.

Children develop skills like walking, talking, and looking after themselves at different rates. Some take longer than others.

If you are concerned that your child is not developing skills, speak to your:

  • child and family health nurse
  • child’s teachers
  • local doctor
  • paediatrician.

Diagnosis

ID can be diagnosed in children under 18 years old by a clinical psychologist or a psychiatrist. 

It is diagnosed using formal tests called “cognitive assessments”.

Cognitive assessments may include activities like: 

  • naming and remembering pictures
  • completing puzzles and patterns
  • answering questions
  • doing independent and everyday living skills. 

Your child's psychologist or psychiatrist will: 

  • gather information from parents, carers, teachers, therapists, and doctors
  • watch your child in everyday settings, like school or child care
  • check for other health conditions related to ID
  • help plan the next steps for getting support.

Treatment

There is no cure or treatment for ID, but early support for learning can make a big difference.

Children with ID will learn and develop new skills at their own pace. They will often need more time and practice than other children of the same age. 

Once your child is diagnosed with ID, their medical team can help you arrange extra support at school and home.

Every child with ID is different. Some may need a little help, while others may need more support in certain areas. 

Support needs can vary depending on the child and the skills they are learning, and may change throughout their life. 

 Management

Support for learning and development

Children with intellectual disability benefit from early, specialised support to help build their skills. They may qualify for funding through the National Disability Insurance Scheme (NDIS) to access therapy and learning support.

Every child has strengths and weaknesses. Building your child’s confidence is key to helping them grow.

Support for families

Each child with ID is different. Some children can grow up to live independently with little help, while others may need more support in daily life.

Getting a diagnosis can be a big change for families, but help and support are available. You can start by discussing your concerns and support options with your family doctor and your child’s school.

Resources and more information

Carers NSW Australia

title
Carers NSW

Email Send email
Phone(02) 9280 4744
Biography
Provides information, education and training, resources and referrals to support carers.
Related Links
Australian Government - Carer Gateway

title
Carer Gateway

Phone1800 422 737
Biography
A national service that provides practical information about services and support available to carers.
Related Links
MDAA

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Multicultural Disability Advocacy Association (MDAA)

Phone1800 629 072
Biography
The peak body for all people in NSW with disability and their families and carers, with a particular focus on those from a culturally and linguistically diverse (CALD) / non English Speaking (NES) background with disability.
Related Links
National Disability Insurance Scheme (NDIS)

title
National Disability Insurance Scheme (NDIS)

Email Send email
Phone1800 800 110
Biography
The National Disability Insurance Scheme (NDIS) supports people with a permanent and significant disability that affects their ability to take part in everyday activities.
Related Links
Parent Line NSW

title
Parent Line NSW

Phone1300 1300 52
Biography
A free telephone counselling and support service for parents and carers with children aged 0 to 18 who live in NSW.
Related Links
RaisingChildren.net.au - The Australian Parenting Website

title
Raising Children: Children with disability

Biography
A free online parenting resource funded by the Australian Government and reviewed by experts.
Related Links
Relationships Australia - New South Wales

title
Relationships Australia

Phone1300 364 277
Biography
Relationship support services including counselling for individuals, couples and families as well as parenting and relationship education.
Related Links
Siblings Australia inc - For siblings of children and adults with disability/illness

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Siblings Australia

Email Send email
Phone(08) 8253 4936
Biography
Support for siblings of children and adults with chronic conditions including disability, chronic illness and mental health issues.
Related Links

Disclaimer

This factsheet is provided for general information only. It does not constitute health advice and should not be used to diagnose or treat any health condition.

Please consult with your doctor or other health professional to make sure this information is right for you and/or your child.

The Sydney Children’s Hospitals Network does not accept responsibility for inaccuracies or omissions, the interpretation of the information, or for success or appropriateness of any treatment described in the factsheet.

© Sydney Children’s Hospitals Network 2025


This factsheet was produced with support from John Hunter Children's Hospital.