Dementia, mental retardation, and competency to make decisions.

The psychiatric literature on competency indicates that a diagnosable psychiatric condition alone does not imply incompetency to make treatment decisions. Nonetheless, it is frequently assumed that individuals who are either mentally retarded or demented are incompetent to make decisions. The authors, focusing on the clinical assessment of judgment and decision making, describe two cases. In both, the patients' judgments were intact. The authors conclude: (1) Diagnosis is not the critical factor in determining competency. (2) The process of judgment and decision making has to be assessed on a case by case basis. (3) Further research is needed to develop clinical instruments to assess judgment.