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What is a Developmental Disability?

Definition of Developmental Disability

The Colorado Rules effective 8/1/2013 (2CCR 503-1, 16.120) define Developmental Disability as a disability that:

A. Is manifested before the person reaches twenty-two (22) years of age;

B. Constitutes a substantial disability to the affected individual, as demonstrated by the criteria below at C.1 and/or C.2; and

C. Is attributable to mental retardation or related conditions, which include cerebral palsy, epilepsy, autism or other neurological conditions, when such conditions result in either impairment of general intellectual functioning or adaptive behavior similar to that of a person with mental retardation.

1. Impairment of “general intellectual functioning' means that the person has been determined to have a Full Scale intellectual quotient equivalent which is two or more standard deviations below the mean (70 or less assuming a scale with a mean of 100 and a standard deviation of 15).

a. A secondary score comparable to the General Abilities Index for a Wechsler Intelligence Scale that is two or more standard deviations below the mean may be used only if a Full Scale score cannot be appropriately derived.

b. Score shall be determined using a norm referenced standardized test of intellectual functioning comparable to a comprehensively administered Wechsler Intelligence Scale or Stanford-Binet intelligence scales, as revised or current to the date of administration. The test shall be administered by a licensed psychologist or a school psychologist.

c. When determining the intellectual quotient equivalent score, a maximum confidence level of ninety percent (90%) shall be applied to the Full Scale score to determine if the interval includes a score of 70 or less, and shall be interpreted to the benefit of the applicant being determined to have a Developmental Disability.

2. 'Adaptive behavior similar to that of a person with mental retardation' means that the person has an overall adaptive behavior Composite or equivalent score that is two or more standard deviations below the mean.

a. Measurements shall be determined using a norm-referenced, standardized assessment of adaptive behaviors that is appropriate to the person’s living environment and comparable to a comprehensively administered Vineland scale of adaptive behavior, as revised or current to the date of administration. The assessment shall be administered and determined by a professional qualified to administer the assessment used.

b. When determining the overall adaptive behavior score, a maximum confidence level of 90 percent shall be applied to the overall adaptive behavior score to determine if the interval range includes a score of 70 or less and shall be interpreted to the benefit of the applicant being determined to have a developmental disability.

D. A person shall not be determined to have a Developmental Disability if it can be demonstrated such conditions are attributable to only a physical or sensory impairment or a mental illness.

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