What is difference between intellectual disability and intellectual/developmental disability?

Understanding I/DD

Intellectual and developmental disabilities (I/DD) are disorders that begin in childhood. They have many causes and symptoms.

Intellectual disabilities are disorders that involve difficulties in intellectual functioning and adaptive behavior and begin before the age of 18. Intellectual functioning involves mental tasks such as learning, reasoning, problem-solving, and so on. It is assessed using an IQ test and is measured in terms of mild, moderate, or severe[1]. Adaptive behavior includes conceptual, social, and practical skills. People who struggle with adaptive behavior may show difficulties with literacy, money management, schedules and time, interpersonal relationships, daily personal care activities, and more [2].

Developmental disability is a broad term that encompasses intellectual disabilities and other lifelong disabilities that begin in childhood before age 22. Developmental disabilities affect intellectual functioning, physical functioning, or both [3]. Examples include Down syndrome, Autism Spectrum Disorder, cerebral palsy, Fragile X Syndrome, and more [4]. Someone with a developmental disability may or may not also have an intellectual disability. Some developmental disabilities may be diagnosed before or shortly after birth, and others may not be diagnosed until later in childhood. Developmental monitoring and screening by a pediatrician can assess whether or not your child is reaching developmental milestones as expected.

Fact Sheets and Frequently Asked Questions

The Centers for Disease Control and Prevention provide a fact sheet on intellectual disabilities in English and Español

The Centers for Disease Control and Prevention provide information on developmental disabilities, including developmental milestones and developmental monitoring and screening. This information is also available en Español. 

The Arc offers an introduction to intellectual disability

Other Resources

Your local Children’s Developmental Services Agency coordinates early intervention services for infants and toddlers up to age 3 who have special needs. 

Alliance Health offers a list of links to I/DD resources in various areas of North Carolina. 

Advocacy and Social Connections

The Arc runs a public policy and legal advocacy page with toolkits and fact sheets to inform people about Medicaid, the Affordable Care Act, and Social Security. 

The North Carolina Council on Developmental Disabilities works to involve people with I/DD and their families in legislative and public policy advocacy.

Wake Network of Care offers a list of links to social and recreational programs for people with I/DD in Wake County and surrounding areas. 

References

What is intellectual disability?

Intellectual Disability

Intellectual disability is a developmental disorder characterised by limitations in intellectual functioning (reasoning, learning, problem-solving) and adaptive behaviour (communication, social and practical skills). This disability originates before the age of 18, and the individual faces more difficulty than others in thinking, learning, and independence.

Intellectual disability is not an illness or disease, but a condition which can occur anytime before, during, or after birth (before 18 years of age). Genetics also play a part as an intellectual disability may occur via the genetic transmission of traits from parents to offspring.

Intellectual Functioning refers to general mental capacity, such as learning, reasoning, problem-solving, etc.

Adaptive Behaviour comprises three skill types – conceptual skills, social skills, and practical skills.

Learn more about our Research Highlights

What is difference between intellectual disability and intellectual/developmental disability?

Exploring the knowledge and competency of Positive Behavioral Support (PBS) amongst Disability professionals in Singapore

Disability professionals provide support to people with learning disabilities with behaviours of concern but the understanding and competency of PBS in Singapore is unknown. The findings indicated that in Singapore, restrictive practice is still prevalent and PBS is not widely practiced in the disability sector.

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What is difference between intellectual disability and intellectual/developmental disability?

Development of the minds client profile checklist for determining The vocational competency of adults with intellectual and developmental disabilities

The present study reports on the development of the Client Profile Checklist (CPC) to assess vocational competency of adults with IDD. The preliminary results suggest that the CPC may be a useful tool for assessing vocational competency of adults with IDD according to the level of support they require.

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What is difference between intellectual disability and intellectual/developmental disability?

Identifying support needs of elderly caregivers of clients with intellectual disabilities in supported employment services in Singapore

The research aims to access the needs of elderly parents as caregivers and the perceived needs of their children with intellectual disabilities through semi-structured interviews. Results talks about child’s care plans and areas to pay attention to for the elderly caregivers.

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What is difference between intellectual disability and intellectual/developmental disability?

Evaluating the effectiveness of support programme for siblings of persons with intellectual and developmental disabilities in Singapore over a five-year period

The research aims to access the effectiveness of a siblings support programme conducted at a large intellectual disability service provider in Singapore. Results were analysed to examine if the programme had met its intended objectives. The paper discusses findings to encourage practitioners to focus on supporting the needs of siblings.

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What is difference between intellectual disability and intellectual/developmental disability?

Preparing adolescent siblings of brothers and sisters with intellectual and developmental disabilities for potential caregiving in future

This study aimed to understand siblings’ feelings and concerns of future caregiving for their brother and sister with ID, and looked at factors that could better prepare siblings for future caregiving. Results show that there are more acceptance among the eldest sibling and worries were more for those without siblings support.

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What is difference between intellectual disability and intellectual/developmental disability?

Implementing Active Support in disability day services: A 6-month prospective study on engagement and behaviours of concern among adults with intellectual disability

This study examines the impact of Active Support in day services for adults with intellectual disability in Singapore, particularly on engagement and behaviours of concern. The Active Support group saw increases in activity engagement and social engagement with staff, and decreases in disengagement and stereotypical behaviours, compared to the control group over time.

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Is there a difference between intellectual disability and developmental disability?

The term "developmental disabilities" is a broader category of often lifelong challenges that can be intellectual, physical, or both. "IDD" is the term often used to describe situations in which intellectual disability and other disabilities are present.

What is the difference between intellectual and developmental?

Developmental disabilities are a group of conditions due to an impairment in physical, learning, language, or behavior areas . These conditions begin during development in youth. The term developmental disability encompasses people with intellectual disabilities but also includes physical disabilities.

What is an intellectual or developmental disability?

An intellectual or developmental disability, also called IDD, includes many severe, chronic conditions that are due to mental and/or physical impairments. IDD can begin at any time, up to 22 years of age. It usually lasts throughout a person's lifetime.