The basics of decision analysis

Historically, decision analysis (DA) arose from economics, psychology, and statistics. Medical and dental applications have developed over the past two decades. While decision psychology explores how people make their decisions, the DA process involves construction of a model and development of insights into the strengths and uncertainties about recommendations derived from analysis of model outputs. Uncertainties are represented as probabilities and values are assigned to desirable or adverse outcomes according to preferences expressed by the decision maker. The model unifies probabilities and values by calculation of the expected value for each decision choice. The decision maker can improve his or her insight into uncertainties in the model by conducting sensitivity analyses, and can take action based on this improved insight. The DA process is illustrated using the decision to take or skip influenza vaccination. People's decision making behavior for this problem has also been analyzed using methods from decision psychology. Distinctions between clinical DA and cost-effectiveness analysis are given, as are caveats about especially complicated subtopics in decision analysis for medical problems. In closing, opportunities for further study of decision analysis are presented.