Generalised reliability characteristics for probabilistic networks.

ABSTRACT

BACKGROUND: In the medical domain, establishing a diagnosis typically amounts to reasoning about the unobservable truth, based upon a set of indirect observations from diagnostic tests. A diagnostic test may not be perfectly reliable, however. To avoid misdiagnosis, therefore, the reliability characteristics of the test should be taken into account upon reasoning. OBJECTIVE: In this paper, we address the issue of modelling the reliability characteristics of diagnostic tests in a probabilistic network. METHOD: To this end, we study the mathematical foundation of a test's characteristics and collate them with the probabilities required for a probabilistic network. RESULTS: We show that the standard reliability characteristics that are generally available from the literature have to be further detailed and stratified, for example by experts, before they can be included in a network. We demonstrate these modelling issues by means of a real-life probabilistic network in oncology.