iors may affect the validity of reports. In such instances, if a same-language or same-culture interviewer is not available, the clinician needs to be very aware of such possible miscommunications in order to obtain a valid interview. The surgeon general’s report emphasizes that more research is needed to better understand how, when, and if culture affects interview-based assessments.
The primary use of adaptive behavior scales in the classification of mental retardation has frequently been confirmatory (i.e., to confirm that a low IQ is associated with delayed acquisition or manifestation of everyday personal and social competencies). This use may result from concerns among clinicians about the robustness of adaptive behavior measures. For the most part, such concerns result from considerations of the structure of measures (e.g., as related to items and other factors mentioned in this section), procedures for obtaining information used to complete the protocols, and issues surrounding informant bias.
Such concerns arise in part because intellectual performance, the other criterion associated with mental retardation, is measured by comprehensive intelligence tests that are the most thoroughly researched forms of psychological assessment (Neisser et al., 1996). Research studies in the past decade that employ adaptive behavior measures have used them as outcome measures or to study the structure or dimensions of adaptive behavior, rather than behavioral development. Clinicians may consequently believe adaptive behavior to be less well understood than intelligence. Nonetheless, there is a rich literature documenting differential outcomes for quality of life, autonomy, and clinical decision making for adaptive behavioral development as measured by existing assessment instruments (Jacobson & Mulick, 1996). Newer adaptive behavior scales evidence more robust psychometric properties than older scales. In this section, we discuss a variety of psychometric features of adaptive behavior scales that have implications for decision making about mental retardation.