Choosing Quality of Life

Intellectual / Developmental Disabilities (I/DD)


Trillium coordinates integrated health care services for adults and children for intellectual and developmental disabilities. Our licensed staff helps approve those services.  Individuals and families without Medicaid may be eligible for state-funded services.

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What is an Intellectual Disability?

A person with an intellectual disability has difficulty:

  • Learning and processing information as quickly as someone without an intellectual disability.
  • Understanding abstract concepts such as money and time.
  • Communicating with others.
  • Planning and organization.

Intellectual disabilities can be mild, moderate, or severe. Someone’s personality, how they handle events, and other health care issues can affect how much support a person needs for daily living. Intellectual disability is thought to affect about 1 - 3% of the population. Of those affected, most have a mild 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).

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

  • Lack of or slow development of motor skills (physical movement), language skills, and self-help skills (like getting dressed), 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. They may observe 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.

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What is a Developmental Disability?

"Developmental Disabilities" is a term that includes intellectual disability, but also includes other disabilities that start in childhood. About 15% of children ages 3 through 17 have one or more developmental disabilities.

Developmental disabilities can affect reasoning and thinking, physical skills, or both. These disabilities appear before age 22 and are likely to be lifelong. Some developmental disabilities are physical issues, such as Cerebral Palsy or Epilepsy. Some individuals may have a condition that includes a physical and intellectual disability.

Your child may have a developmental disability if they have:

  • Delay in meeting fundamental milestones (such as walking and talking)
  • Issues with sight or hearing
  • Low birth weight or premature birth 
  • Lose skills or stop doing things they could do before
  • Not respond emotionally when parent/caregiver leaves the room

Intellectual Developmental Disability (I/DD) Services Array Brochure: has more information on the services provided for individuals with Intellectual/Developmental Disabilities.

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