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Urgent Message:
Nash County residents:
Effective date has been moved to July 1, 2017. See more details here
Urgent Message:
Nash County residents:
Effective date has been moved to July 1, 2017. See more details here

Intellectual/Developmental Disabilities (I/DD)


Trillium serves approximately 2,450 adults and children annually who seek services for Intellectual and/or Developmental Disabilities (I/DD).   Individuals and families without Medicaid may be eligible for state-funded services. 

To ensure individuals and families receive the services they need in a timely manner, we employ clinically trained staff to manage and authorize those services. 

What is Intellectual Disability?

Intellectual disability can be mild, moderate or severe.  Factors such as personality, coping strategies and the presence of other disabilities (motor, social or sensory) will influence a person's requirement for support with daily living. Intellectual disability is thought to affect about 1 - 3% of the population. Of those affected, the majority have mild intellectual disability.

Every person is unique, regardless of their IQ score. Everyone has their own personality and areas of ability and areas of difficulty. Generally a person with an intellectual disability has difficulty learning and processing information as quickly as someone without an intellectual disability; grasping abstract concepts such as money and time; understanding interpersonal interactions; and manipulating the ideas and concepts required for planning and organization.

  • Intellectual functioning: Also known as IQ (intelligence quotient), this refers to a person’s ability to learn reason, make decisions, and solve problems.  IQ is measured by an IQ test. The average IQ is 100. A person is considered to have an intellectual disability if he or she has an IQ of less than 70 to 75.
  • Adaptive behaviors: These are skills necessary for day-to-day life, such as being able to communicate effectively, interact with others, and take care of oneself

Your child may have an intellectual disability if you notice any of the following:

  • Lack of or slow development of motor skills, language skills, and self-help skills, especially when compared to peers
  • Failure to grow intellectually or continued infant-like behavior
  • Lack of curiosity
  • Problems keeping up in school
  • Failure to adapt (adjust to new situations)
  • Difficulty understanding and following social rules

To measure a child’s adaptive behaviors, a specialist will observe the child’s skills and compare them to other children of the same age. Things that may be observed include how well the child can feed or dress himself or herself; how well the child is able to communicate with and understand others; and how the child interacts with family, friends, and other children of the same age.

What Causes Intellectual Disability? There are many causes of intellectual disability, but doctors find a specific reason in only 25% of cases.  The most common syndromes associated with intellectual disabilities are Autism, Down Syndrome, Fragile X Syndrome, and Fetal Alcohol Spectrum Disorder (FASD). 

Causes of Intellectual Disability Can Include: 

  • Infections (present at birth or occurring after birth)
  • Genetic Conditions
  • Environmental
  • Metabolic (such as hyperbilirubinemia, very high bilirubin levels in babies)
  • Nutritional (such as malnutrition)
  • Toxic (intrauterine exposure to alcohol other drugs)
  • Trauma (before and after birth)
  • Unexplained (this largest category is for unexplained occurrences of intellectual disability)

What is a Developmental Disability?

"Developmental Disabilities" is an umbrella term that includes intellectual disability but also includes other disabilities that are apparent during childhood. 

Developmental disabilities are those that can be cognitive or physical or both. The disabilities appear before the age of 22 and are likely to be lifelong. Some developmental disabilities are largely physical issues, such as Cerebral Palsy or Epilepsy. Some individuals may have a condition that includes a physical and intellectual disability.

Resources & Links:



Autism Ribbon

Autism Awareness Month

In order to highlight the growing need for concern and awareness about autism, the Autism Society has celebrated National Autism Awareness Month since the 1970s. This is a special opportunity for knowledgeable people and organizations to educate the public about autism and issues within the autism community.