ABSTRACT
The chapter focuses on the methodologies and challenges of prior elicitation, a process that enables translation of expert knowledge and judgment into a probability distribution—a quantitative belief distribution. It provides an extended example and discusses how the distributions can be utilized to improve the drug development process. The use of expert opinion in the construction of a prior probability distribution—prior elicitation—is a multi-disciplinary process. The probability distribution will reflect what the expert believes about the value of the quantity as well as the uncertainty of that belief. Prior elicitation requires participation of several experts, ideally with a variety of backgrounds and beliefs. The framework should cover all aspects of the elicitation including the planning, execution, and documentation of the elicitation. The facilitator guides the experts through the process, ensuring that all viewpoints are shared and debated and at the end presents the fitted probability distribution representing the experts’ beliefs. Good measurement practice requires a well-defined protocol.
