Abstract: A decision support system for the selection of a diagnostic or therapeutic test or intervention, herein called studies, is supported by identifying a relative number of cases in which significant results were obtained in studies having the same indications. In particular, an ordering physician requests a study for a patient and specifies indications for the study, such as symptoms and a potential diagnosis. The number of studies performed, including those on other patients, for which results were significant for the same indications out of the total number of studies performed for the same indications is provided as feedback to the ordering physician. This feedback relates actual patient results to the appropriateness of the study. A decision support system in a health care information management system receives, from an ordering physician, an order for a study to be performed on a specified patient and indications for the study.