Intellectual disability

A person with an intellectual disability may have difficulty learning and managing daily living skills. This is because their cognitive (thought-related) processing is impaired. Children and young people have different abilities and develop at different rates. Some children find learning new skills or information difficult. This may be because they have an intellectual disability.

A person is said to have an intellectual disability if they have both the following before they are 18 years of age:

• An IQ below 70 (average IQ is 100)
• Significant difficulty with daily living skills including looking after themselves, communicating and taking part in activities with others.

About two to three per cent of the population have an intellectual disability. This is more than 100,000 Victorians, but not all seek or receive disability services.

Common characteristics

Every person is unique, regardless of their IQ score. Everyone has their own personality and areas of ability and areas of difficulty. Generally speaking, a person with an intellectual disability:

• Learns and processes information more slowly than people without an intellectual disability
• Has difficulty with abstract concepts, such as money and time
• Has difficulty understanding the subtleties of interpersonal interactions.

Needs depend on individual factors

Arbitrary categories of mild, moderate, severe and profound levels of intellectual disability are defined on the basis of IQ scores. These levels give some guide to the level of support someone might need, but the way the person functions in their life also depends on other factors including:

• Personality
• Coping skills
• Other disabilities – for example, physical, social or sensory
• The amount of support offered by family, friends and the community
• What is demanded of them in different situations – for example, home or work.

People with a mild intellectual disability

A mild intellectual disability is defined as an IQ between 50 and 70. A person with a mild intellectual disability:

• Can participate in and contribute to their families and their communities
• Will have important relationships in their lives
• May find the subtleties of interpersonal relationships and social rules difficult to fully understand. They may sometimes behave awkwardly or inappropriately in social situations
• May marry and raise children with the support of family, friends and support services
• May have a job, in either open or supported employment
• May live and travel independently but may need support and help to handle money and to plan and organise their daily life
• May learn to read and write, with appropriate teaching. People who have an intellectual disability are likely to have difficulty with academic learning and their reading and writing may be at a basic level. Some people may not have had the educational support they needed to learn to read or write and may be self-conscious about this. It is important to be sensitive when asking people to read information or complete written forms.

People with a moderate intellectual disability

A moderate intellectual disability is defined as an IQ between 35 and 50. A person with a moderate intellectual disability:

• Will have important relationships in their life and will probably form valued and lasting friendships
• Will enjoy a range of activities with their families, friends and acquaintances
• May be able to learn to travel on regular public transport routes with specific training, but will have difficulty planning trips and handling money. They may have great difficulty problem solving when unexpected events occur
• May learn to recognise some words in context, such as common signs including ‘Ladies’, ‘Gents’ and ‘Exit’
• Will be able to make choices and understand daily schedules or future events if provided with visual prompts such as daily timetables and pictures of planned events
• Will need lifelong support in the planning and organisation of their lives and activities
• May develop independence in personal care, such as toilet hygiene, dressing and bathing. Independence in these tasks will depend on opportunities to learn and practise these tasks, and whether or not the person has other disabilities, such as cerebral palsy.

People with a severe or profound intellectual disability

A severe intellectual disability is defined as an IQ between 20 and 35. A profound intellectual disability is defined as an IQ below 20. A person with a severe or profound intellectual disability:

• Will usually recognise familiar people and may have strong relationships with key people in their lives
• Is likely to have little or no speech and will rely on gestures, facial expression and body language to communicate needs or feelings. Communication systems for people with this level of disability generally rely on photographs or objects to support understanding. For example, a cup or a photograph of a cup may be used with the spoken question: ‘Would you like a drink?’
• Will require lifelong help with personal care tasks, communication and accessing and participating in community facilities, services and activities.

Communication tips

Tips that may help when talking with someone who has an intellectual disability include:

• Make sure you have the person’s attention. Use their name, gain eye contact or respectfully touch their arm.
• Start by assuming a person can understand you, then adjust your level of communication according to their response.
• Ask the person how they would like to communicate if they do not use speech. This could include using communication aids or devices, answering with a way of saying ‘yes’ or ‘no’ to questions (for example, using eye gaze, or head or hand movements), sign language, gestures or facial expressions. If you are not able to understand the person, you may need to ask whoever is accompanying them to assist you.
• Use appropriate language for the person and the situation – for example, simple, clear words and short uncomplicated sentences. If the person concerned is an adult, do not speak as though they are a child.
• Use visual information such as pictures, diagrams, signs, objects, gestures or miming to improve understanding.
• Use a respectful tone and volume. If the person does not understand you, try a different way of providing the information or asking the question – don’t assume that raising the volume of your voice will help!
• Don’t rush. Allow the person the time to listen, process your words and formulate a response. Waiting patiently conveys interest in and respect for what they will say.
• Check if they have been able to understand what you have said by asking them to rephrase in their own words. Do not simply ask, ‘Do you understand?’ as people will often say ‘yes’ to avoid embarrassment or because it is the answer they think you want to hear.
• If you think you have not been understood, try repeating your message more slowly or using different words. It is your responsibility to make sure your message is understood accurately.
• If you don’t understand the other person, do not pretend to understand. Be honest and take responsibility for any communication breakdowns. For example, say: ‘I’m sorry, I don’t understand what you’re telling me. Would you please tell me again?’
• If you cannot understand or be understood, try another approach. Is there another way you can communicate what you want to say? Ask if it’s okay to involve someone who is familiar to the person (a family member or support worker).

Where to get help

• Your doctor
• The Centre for Developmental Disability Health Victoria Tel. (03) 9902 4467
• Scope Tel. (03) 9843 3000
• Yooralla Community Learning and Living Centre Tel. (03) 9916 5800 or 1300 885 886 (Victoria Only); TTY (03) 9916 5899
• Disability Intake and Response Service Tel. 1800 783 783

Things to remember

• A person with an intellectual disability may need assistance with daily living skills such as self-care, communication and community access and participation.
• Categories of mild, moderate, severe and profound levels of intellectual disability are arbitrarily defined on the basis of IQ score. Factors such as personality, presence of other disabilities and social support also play important roles in how the person functions in their daily life.
• If you’re not sure whether a person is able to understand you, assume they can and then check their understanding and adjust your language and communication style accordingly.
• Always demonstrate respect for the person and communicate in ways that acknowledge the age of the person and the value of their contribution.

You might also be interested in:

• Disability - support for families.
  
• Disability - support services.
  
• Disability and sexual issues.
  
• Intellectual disability - facts and figures.
  
• Sex education for children with intellectual disabilities - tips for parents.
  
• Sex education - young people with intellectual disabilities.
  

Want to know more?

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This page has been produced in consultation with and approved by:

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Centre for Developmental Disability Health Victoria

Fact sheet currently being reviewed.
Last reviewed: March 2012

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<a href="http://www.betterhealth.vic.gov.au/bhcv2/bhcarticles.nsf/pages/Intellectual_disability?open">Intellectual disability - Better Health Channel</a><br/>
A person with an intellectual disability may have difficulty learning and managing daily living skills. This is due to impaired cognitive (thought) processing before the age of 18 years resulting in an IQ below 70. However, everyone is unique. How a person functions in their daily life depends on many factors not just IQ level.

Content on this website is provided for education and information purposes only. Information about a therapy, service, product or treatment does not imply endorsement and is not intended to replace advice from your qualified health professional. Content has been prepared for Victorian residence and wider Australian audiences, and was accurate at the time of publication. Readers should note that over time currency and completeness of the information may change. All users are urged to always seek advice from a qualified health care professional for diagnosis and answers to their medical questions.

For the latest updates and more information, visit www.betterhealth.vic.gov.au

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