A method, apparatus and computer program product for using machine learning to evaluate medical risks are described. A graphical user interface is provided for entering a set of patient symptoms for a first patient. A query is sent to a medical system containing the set of patient symptoms. A set of causal factors related to the patient symptoms and a set of association link strengths are received in response. Each association link strength is representative of a strength of a relationship between a respective patient symptom and a respective causal factor. The graphical user interface displays the set of patient symptoms and the set of causal factors according to the respective association link strength to show which causal factors have likely caused the patient symptoms for the first patient and are relevant for selecting among different treatment regimens. The association link strengths are calculated by a set of association link formulas learned by a machine learning system using a set of symptoms and a set of causal factors.