A MATHEMATICAL APPROACH TO MEDICAL DIAGNOSIS - APPLICATION TO POLYCYTHEMIC STATES UTILIZING CLINICAL FINDINGS WITH VALUES CONTINUOUSLY DISTRIBUTED

Certain clinical findings, largely laboratory data, which help to distinguish the various polycythemic states, are continuously distributed. These continuous distributions were used as probability functions from which elements of Bayes' formula for conditional probability were derived. This formula was written into a computer program which calculates a probability value for each of the diagnostic possibilities. A preliminary trial of the program employing this technique was applied to 103 cases that were either normal or known to have polycythemia rubra vera. When presented with the initial patient data the mathematical probability diagnosis was correct 95% of the time. Three hematologists were 76% correct whereas three general practitioners were correct in 65% of the same cases. © 1969.