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Intellectual/Developmental Disability (I/DD)

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. 




  • Oct 31 2019