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Intellectual and Developmental Disabilities:

How are Intellectual and Developmental Disabilities diagnosed?

Intellectual and Developmental Disabilities (formerly referred to as mental retardation) are diagnosed by looking at two main things. These are:

  • The ability of a person’s brain to learn, think, solve problems, and make sense of the world (called IQ or intellectual functioning); and
  • Whether the person has the skills he or she needs to live independently (called adaptive behavior, or adaptive functioning).

Intellectual functioning, or IQ, is usually measured by an IQ test. The average score is 100. People scoring below 70 to 75 are thought to have intellectual and developmental disabilities. To measure adaptive behavior, professionals look at what a child can do in comparison to other children of his or her age. Certain skills are important to adaptive behavior. These are:

  • Daily living skills, such as getting dressed, going to the bathroom, and feeding one’s self;
  • Communication skills, such as understanding what is said and being able to answer;
  • Social skills with peers, family members, adults, and others.

Providing services to help individuals with intellectual and developmental disabilities has led to a new understanding of how we define intellectual and developmental disabilities. After the initial diagnosis of intellectual and developmental disabilities is made, we look at a person’s strengths and weaknesses. We also look at how much support or help the person needs to get along at home, in school, and in the community. This approach gives a realistic picture of each individual. It also recognizes that the “picture” can change. As the person grows and learns, his or her ability to get along in the world grows as well.

To be eligible for intellectual and developmental disabilities services in Texas, an individual must be part of the intellectual and developmental disabilities priority population established by Texas law. As Texas’ population continues to grow, the number of people requiring intellectual and developmental disabilities services increases – sometimes faster than the state can expand services. Therefore, services and supports are provided for those individuals who need them the most- those individuals with the greatest severity of intellectual and developmental disabilities. Specifically, this population is comprised of people meeting one or more of the following descriptions:

text-justify”Intellectual and Developmental Disabilities as defined by Section 591.003 (13), Title 7, of the Texas Health and Safety Code and includes those persons who possess the following needs:

  • Autism and Pervasive Developmental Disorders as defined in the current edition of the Diagnostic and Statistical Manual (DSM).and
  • Developmental delays in children under 3 years of age, which leads to eligibility for Early Childhood Intervention Services.
  • Eligibility for OBRA ‘87 mandated services forintellectual and developmental disabilities or a related condition as per specific legislation.