ISSUES IN THE TAXONOMY OF PSYCHOPATHOLOGY IN MENTAL-RETARDATION

Several factors appear to impede the development of a valid taxonomy o f psychopathology in children and adolescents with mental retardation. These include (a) the lack of a widely accepted definition of psychop athology in mental retardation, (b) disagreement on the nature of the relationship between mental retardation and psychopathology, and (c) i nsufficient evidence for the reliability and validity of current DSM o r ICD systems in this population. In this article, we offer a definiti on of psychopathology in children with mental retardation; review conc epts of the relationship between psychopathology and mental retardatio n; argue that in moving toward a valid taxonomy factors to be consider ed should include data from multivariate studies, findings related to behavior phenotypes, and diagnostic considerations with stereotypic be havior and self-injury organic brain syndromes and pervasive developme ntal disorders. Finally, we outline a research strategy that may serve as a useful framework for developing a valid taxonomy of psychopathol ogy in this population.