Quantitative and qualitative approaches to reasoning under uncertainty in medical decision making

Medical decision making frequently requires the effective management and communication of uncertainty and risk. However a tension exists between classical probability theory, which is precise and rigorous but which people find non-intuitive and difficult to use, and qualitative approaches which are ad hoc but can be more versatile and easily comprehensible. In this paper we review a range of approaches to uncertainty management, then describe a logical approach, argumentation, which subsumes qualitative as well as quantitative representations and has a clear formal semantics. The approach is illustrated and evaluated in five decision support applications.