On the definition and classification of mental retardation.

A classification system of mental retardation was proposed based on etiology and IQs at least 2 SDs below the population mean. Social competence and performance capabilities of individuals with subaverage IQs were removed from definitional status and given prominence as correlates of class membership. The reliance on IQs to define mental retardation was predicated on the view that the behavioral sciences currently have no better measure of intellectual functioning, although promising efforts continue. The proclivity to avoid using the label "mentally retarded" was seen as ill-conducive to the betterment of knowledge in the field and detrimental to unlabeled individuals who are denied access to beneficial services.