Sensitivity Analysis on a Chance Node with More Than Two Branches

Abstract

Sensitivity analysis is an essential part of decision analysis. The literature on medical decision analysis suggests the use of two-branch chance nodes in decision trees to avoid logical inconsistencies during sensitivity analysis. The authors show that the two- branch decomposition is not appropriate for sensitivity analysis when multiple out comes from a single state cannot be disentangled into a sensible sequence of events. They recommend retaining the natural structure of the tree and propose two sensitivity- analysis methods for use on chance nodes with three or more branches. Key words: sensitivity analysis; decision analysis; decision tree; probability. (Med Decis Making 1999;19:499-502)