Intellectual Disability
Image for Intellectual Disability
Disability Categories Main Page
Additional Pages:
Autism
Deaf-Blindness
Deafness
Developmentally Delayed
Emotional Disturbance
Fuctional Delay
Hearing Impairment
Intellectual Disability
Intellectually Gifted
Multiple Disabilities
Orthopedic Impairment
Other Health Impairment
Specific Learning Disabilities
Speech or Language Impairment
Traumatic Brain Injury
Visual Impairment


1. Definition

Intellectual disability is characterized by significantly impaired intellectual functioning, existing concurrently with deficits in adaptive behavior and manifested during the developmental period that adversely affect a child’s educational performance.

2. Evaluation

The characteristics as identified in the Intellectual disability Definition are present.

Evaluation Procedures

Evaluation of Intellectual disability shall include the following:

a. Assessment of intelligence/cognitive abilities, adaptive behaviors at school and in the home, and developmental assessment as follows:

(1) intellectual functioning, determined by appropriate assessment of intelligence/cognitive abilities which results in significantly impaired intellectual functioning, which is two or more standard deviations below the mean, with consideration given to the standard error of measurement for the test at the 68th percent confidence level, on an individually administered, standardized measure of intelligence;

(2) significantly impaired adaptive behavior in the home or community determined by:

(a) a composite score on an individual standardized instrument to be completed with or by the child’s principal caretaker which measures two standard deviations or more below the mean. Standard scores shall be used. A composite age equivalent score that represents a 50% delay based on chronological age can be used only if the instrument fails to provide a composite standard score, and

(b) additional documentation, when appropriate, which may be obtained from systematic documented observations, impressions, developmental history by an appropriate specialist in conjunction with the principal caretaker in the home, community, residential program or institutional setting; and

(3) significantly impaired adaptive behavior in the school, daycare center, residence, or program as determined by:

(a) systematic documented observations by an appropriate specialist, which compare the child with other children of his/her chronological age group. Observations shall address age-appropriate adaptive behaviors. Adaptive behaviors to be observed in each age range include:

i. birth to 6 years – communication, self-care, social skills, and physical development;

ii. 6 to 13 years – communication, self-care, social skills, home living, community use, self-direction, health and safety, functional academics, and leisure;

Disability Eligibility Standards 16

iii. 14 to 21 years – communication, self-care, social skills, home-living, community use, self-direction, health and safety, functional academics, leisure, and work; and

(b) when appropriate, an individual standardized instrument may be completed with the principal teacher of the child. A composite score on this instrument shall measure two standard deviations or more below the mean. Standard scores shall be used. A composite age equivalent score that represents a 50% delay based on chronological age can be used only if the instrument fails to provide a composite standard score; and

(4) Assessments and interpretation of evaluation results in evaluation standards 2.a.(1), 2.a.(2), and 2.a.(3) shall take into account factors that may affect test performance, including:

(a) limited English proficiency;

(b) cultural factors;

(c) medical conditions that impact school performance;

(d) environmental factors;

(e) communication, sensory or motor disabilities; and

(f) difficulties in these areas cannot be the primary reason for significantly impaired scores on measures of intellectual functioning, home, and school adaptive behavior.

b. Developmental history which indicates delays in cognitive/intellectual abilities (intellectual impairment) manifested during the developmental period (birth to 18) as documented in background information and history and a current demonstration of delays present in the child's’ natural (home and school) environment.

c. Documentation, including observation and/or assessment of how Intellectual disability adversely impacts the child’s educational performance in his/her learning environment.

Evaluation Participants

Information shall be gathered from the following persons in the evaluation of Intellectual disability:

(1) the parent;

(2) the child’s general education classroom teacher;

(3) a licensed special education teacher;

(4) a licensed school psychologist, licensed psychologist, licensed senior psychological examiner, or licensed psychological examiner; and

(5) other professional personnel, as indicated.