Life-span development of institutionalized and community-based mentally retarded residents.

Life-span development of mentally retarded residents in institution and community settings was examined. Results showed that significant growth in adaptive behavior occurred for all groups of residents regardless of their level of retardation. Furthermore, the shapes of these growth curves were parallel across the different levels of retardation over the age range studies (5 to 50 years). Measures of the quality of the environment were available for institutionalized residents and were found to be unrelated to adaptive behavior growth; however, environmental quality was associated with initial levels of adaptive behavior, suggesting that for institutionalized residents, adaptive behavior competence may determine the type of environment provided.