title: The Relation Between Intellectual Functioning and Adaptive Behavior in the Diagnosis of Intellectual Disability.
abstract: Intellectual disability originates during the developmental period and is characterized by significant limitations both in intellectual functioning and in adaptive behavior as expressed in conceptual, social, and practical adaptive skills. In this article, we present a brief history of the diagnostic criteria of intellectual disability for both the DSM-5 and AAIDD. The article also (a) provides an update of the understanding of adaptive behavior, (b) dispels two thinking errors regarding mistaken temporal or causal link between intellectual functioning and adaptive behavior, (c) explains that there is a strong correlational, but no causative, relation between intellectual functioning and adaptive behavior, and (d) asserts that once a question of determining intellectual disability is raised, both intellectual functioning and adaptive behavior are assessed and considered jointly and weighed equally in the diagnosis of intellectual disability. We discuss the problems created by an inaccurate statement that appears in the DSM-5 regarding a causal link between deficits in intellectual functioning and adaptive behavior and propose an immediate revision to remove this erroneous and confounding statement.
authors.affiliation: Marc J. Tassé, The Ohio State University, Nisonger Center, Department of Psychology & Psychiatry.
authors.forename: Marc J
authors.initials: MJ
authors.lastname: Tassé
authors.affiliation: Ruth Luckasson, University of New Mexico, Department of Special Education; and.
authors.forename: Ruth
authors.initials: R
authors.lastname: Luckasson
authors.affiliation: Robert L. Schalock, Hastings College, Department of Psychology.
authors.forename: Robert L
authors.initials: RL
authors.lastname: Schalock
mesh_terms: D000223:Adaptation, Psychological; D039721:Diagnostic and Statistical Manual of Mental Disorders; D006801:Humans; D008607:Intellectual Disability / Q000175:diagnosis* / Q000523:psychology*; D010344:Patient Advocacy; D012952:Societies
keywords: DSM-5; adaptive behavior; definitions of intellectual disability; diagnosis; intellectual disability; intellectual functioning; mental retardation