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Developmental Disability Definition

According to the CDC a Developmental Disability is a disability that manifests before the person reaches twenty-two (22) years of age, constitutes a substantial disability to the affected individual, and is attributable to mental retardation or related conditions which include cerebral palsy, epilepsy, autism or other neurological condition when such condition results in impairment of general intellectual functioning or adaptive behavior similar to that of a person with mental retardation.

Impairment of general intellectual functioning means that the person has been determined to have an 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), as measured by an instrument which is standardized, appropriate to the nature of the person’s disability, and administered by a qualified professional. The standard error of measurement of the instrument should be considered when determining the intellectual quotient equivalent. When an individual’s general intellectual functioning cannot be measured by a standardized instrument, then the assessment of a qualified professional shall be used.

“Adaptive behavior similar to that of a person with mental retardation” means that the person has overall adaptive behavior which is two or more standard deviations below the mean in two or more skill areas (communication, self-care, home living, social skills, community use, self-direction, health and safety, functional academics, leisure, and work), as measured by an instrument which is standardized, appropriate to the person’s living environment, and administered and clinically determined by a qualified professional.

These adaptive behavior limitations are a direct result of, or are significantly influenced by, the person’s substantial intellectual deficits and may not be attributable to only a physical or sensory impairment or mental illness.

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