Decision­Theoretic Refinement Planning in Medical Decision Making: Management of Acute Deep Venous Thrombosis


Peter Haddawy, Ph.D. AnHai Doan, B.S. Charles E. Kahn, Jr., M.D.

Department of Electrical Engineering and Computer Science, University of Wisconsin ­ Milwaukee, Milwaukee, Wisconsin 53201.

Department of Radiology, Medical College of Wisconsin, Milwaukee, Wisconsin 53226

Abstract

Decision­theoretic refinement planning is a new technique for finding optimal courses of ac­ tion. The authors sought to determine whether this technique could identify optimal strate­ gies for medical diagnosis and therapy. An existing model of acute deep venous thrombosis (DVT) of the lower extremities was encoded for analysis by the drips decision­theoretic refinement planning system. The encoding represented 6,206 possible plans. The drips planner used abstraction techniques to eliminate 5,551 plans (89%) from consideration with­ out examining them explicitly. It determined that, given the parameters specified, the most cost­effective management strategy was ``no tests, no treatment.'' This result differed from the published result of ``perform ultrasonography, treat if positive''; drips had revealed an error in the reference article's manually constructed decision trees. We conclude that decision­theoretic planning is useful for examining large medical decision problems, and that it can help reduce errors introduced by manual construction of decision trees.