A READERS GUIDE TO SURGICAL DECISION-ANALYSIS

BACKGROUND: Studies using decision analysis appear increasingly often in the surgical literature. Because readers and reviewers may be unfam iliar with decision analysis, we review the technique and provide guid ance on its interpretation. STUDY DESIGN: Review article. RESULTS: Dec ision analysis is a systematic approach to structuring a decision, col lecting relevant information about the probability and relative value of outcomes, and making quantitative recommendations. Decision analysi s includes the following basic components: (1) the decision model, (2) the probabilities of clinical outcomes in the model, (3) the utilitie s of clinical outcomes, and (4) the analysis and interpretation. To cr itically interpret the results of a decision analysis, readers must co nsider the validity of each component. The model should include all re levant clinical strategies and all important clinical outcomes. Probab ility estimates, whether derived from published studies or based on '' clinical consensus,'' should be in general agreement with the reader's clinical experience. Utilities (values assigned to outcomes) are ofte n expressed in terms of quality-adjusted life expectancy. Methods used to estimate life expectancy and to adjust for quality of life must be scrutinized carefully. Within the analysis, readers should consider t he effect of varying uncertain variables in the model (sensitivity ana lysis) and, thus, the stability of the results. Finally, readers must assess whether the magnitude of expected benefit from the favored clin ical strategy is clinically important. CONCLUSIONS: As decision analys is becomes more frequently used to influence clinical policy in surger y, surgeons must learn to examine the technique more critically.