Abstract: Systems, methods and computer program products are provided for identifying members of a population having a specified disease state. First and second sets of medical events associated with a disease state are identified. Each member of first and second population subsets have at least one medical event from the first and second sets of medical events, respectively. A third population subset is created comprising members of the first population subset who are not members of the second population subset. A specificity rating, indicating how often a respective medical event occurred within the second population subset relative to the third population subset, is assigned to each medical event associated with members of the second population subset. A third set of medical events associated with members of the second population subset is identified, each of the identified medical events having a specificity rating above the selected threshold.