Valid informed consent is the bedrock of ethical human research, but decisional capacity for the purpose of informed consent has been questioned in persons afflicted with schizophrenia (sz). We have used the MacCAT-CR to evaluate the four elements of valid informed consent in sz patients (understanding, appreciation, reasoning, and choice), and demonstrated that in patients with poor decisional capacity there is significant improvement following a standardized intervention. However, improvement was mainly observed in the understanding component, and not in appreciation or reasoning. In this application we propose to further develop the field's ability to reliably assess and improve decisional capacity, especially appreciation and reasoning, as well as therapeutic misconception (TM), which is inadequately represented in existing procedures. We will also describe the degree to which clinical trial participants retain or forget consent information over the course of participation in lengthy protocols. Using tests of decision-making behavior we will address whether schizophrenia patients bring to the process of informed consent any biases, which might influence their appreciation and reasoning, and whether they are more or less attracted than controls to especially risky choices. If successful, the proposed work will provide: 1] a more comprehensive and reliable test of informed consent validity than is currently available; 2] data supporting either the use of a targeted intervention or repeated consent disclosure to ensure adequate appreciation and reasoning and to minimize TM; 3) a description of how well schizophrenia patients are able to retain consent information during clinical trial participation; and 4) data determining the degree to which schizophrenia patients deviate from healthy controls in decision-making behavior and treatment of risk. ? ? ?