It is money that matters: decision analysis and cost-effectiveness analysis.

Clinical decisions must be made, often under circumstances of uncertainty and limited resources. Decision analysis and cost-effectiveness analysis are methodologic tools that allow for quantitative analysis and the optimization of decision-making. These methods can be useful for decisions regarding individual patient evaluation and treatment options or in formulating healthcare policy. We overview the methodology of expected value decision analysis and of cost-effectiveness analysis, including cost-identification, cost-effectiveness, cost-benefit, and cost-utility analyses. Examples are provided of these methods and a user's guide to cost-effectiveness analysis is outlined.