Intellectual and Developmental Disabilities
This chapter addresses intellectual disabilities (ID) and developmental disabilities (DD), acknowledging an overlap concerning the populations of individuals who may be so identified. There is a distinct subgroup of those who might be identified as ID but who would not be technically considered DD; this would include some individuals who may be considered mildly intellectually disabled. Hundreds of causes have been identified for IDD, but only in about 50% of the cases can a specific biological factor be identified. The chapter focuses solely on examples of genetic transmission, chromosomal anomalies, fetal alcohol spectrum disorders, and psychosocial considerations. Polloway and Smith et al. addressed considerations and provided a national perspective on the prevalence of IDD within the public schools and examined placement and educational programs. The chapter also discusses considerations related to individuals with IDD throughout their educational careers. Attention is focused on early childhood, elementary and secondary school, and transitional concerns to adulthood.