There are two definitions, federal and state, that determine the type of services and eligibility of individuals with developmental disabilities. The state definition known as the Lanterman Disabilities Services Act (W&I Code Sec 4512(a)) defines the term developmental disability as a severe and chronic disability that is attributable to a mental or physical impairment. The disability must begin before the 18th birthday, be expected to continue indefinitely and present a substantial disability. Also, the disability must be due to one of the following conditions:
- Mental retardation
- Cerebral Palsy
- A disabling condition closely related to mental retardation or requiring similar treatment.
The federal definition follows the Developmental Disabilities Assistance and Bill of Rights Act Amendments of 1994 and defines a developmental disability as a severe, chronic disability of an individual 5 years of age or older that:
- is attributable to a mental or physical impairment or combination of mental and physical impairments
- is manifested before the individual attains age 22
- is likely to continue indefinitely
- results in substantial functional limitations in three or more of the following areas of major life activity: self-care, receptive and expressive language, learning, mobility, self-direction, capacity for independent living, and economic self-sufficiency
- reflects the individual's need for a combination and sequence of special, interdisciplinary, or generic services, supports, or other assistance that is of lifelong or extended duration and is individually planned and coordinated, except that such term, when applied to infants and young children means individuals from birth to age 5, inclusive, who have substantial developmental delay or specific congenital or acquired conditions with a high probability of resulting in developmental disabilities if services are not provided.