The purpose of this article is to move the field of intellectual and closely related developmental disabilities (IDD) towards a better understanding of evidence and evidence-based practices. To that end, we discuss (a) different perspectives on and levels of evidence, (b) commonly used evidence-gathering strategies, (c) standards to evaluate…

The purpose of this study was to explore the cross-cultural validity of the Self-Determination Inventory: Student Report, a newly developed measure of self-determination grounded in Causal Agency Theory. The tool was translated to Spanish and administered to American and Spanish adolescents. The sample was structured to include adolescents with…

This study investigated the effects of a training package (written manual, individual training session, and ongoing verbal feedback) on middle school peer tutors' use of embedded, constant time delay procedures and on the learning outcomes for students with significant cognitive disabilities in general education settings. The study data showed…

Because persons with mental retardation cannot be executed for murder, the diagnosis becomes a life and death matter. The American Association on Mental Retardation (now the American Association on Intellectual and Developmental Disabilities) and other associations agree that IQ alone is an insufficient criterion and adaptive functioning also…